Wednesday, May 23

Plenary II: Kerry Vahala

Plenary II: Kerry Vahala

Paper Title Authors
PL2: Towards Integrated Optical Time Standards and Frequency Synthesizers

Kerry Vahala

Abstract: Communication systems leverage the respective strengths of optics and electronics to convey high-bandwidth signals over great distances.  These systems were enabled by a revolution in low-optical-loss dielectric fiber, complex integrated circuits as well as devices that link together the optical and electrical worlds.  Today, another revolution is leveraging the advantages of optics and electronics in new ways.  At its center is the laser frequency comb which provides a coherent link between these two worlds. Significantly, because the link is also bidirectional, performance attributes previously unique to electronics and optics can be shared. The end result has been transformative for time keeping, frequency metrology, precision spectroscopy, microwave-generation, ranging and other technologies. Even more recently, low-optical-loss dielectrics, now in the form of high-Q optical resonators, are enabling the miniaturization of frequency combs. These new `microcombs’ can be integrated with electronics and other optical components to potentially create systems on-a-chip.  I will briefly overview the history and elements of frequency combs as well as the physics of the new microcombs. Efforts underway to develop integrated optical clocks and integrated optical frequency synthesizers using the microcomb element are also described.


MeerKAT and Components - Big and Small

Moderator: Gregory Weaver

Paper Title Authors Executive Summary
SSW1: Robust Time Scale Design and Implementation for Telescope Time in a Remote Desert Environment Johan Burger, Renier Siebrits, Grant Adams, Romeo Gamatham, Thomas Abbott, Francois Kapp, Nontobeko Mnyandu, Vereese van Tonder, Marc Welz, Angelo Syce, Peter Rogers A clock ensemble for tracking time for a next generation radio telescope (MeerKAT) is being built, to enable robust timing over long periods (~ 10 years) in a remote desert environment at the phase center of the MeerKAT w.r.t. UTC
SSW2: 2.5 GHz Highly-Linear Magnetic-Free Microelectromechanical Resonant Circulator Yao Yu, Flavius Pop, Giuseppe Michetti, Piotr Kulik, Michele Pirro, Ahmed Kord, Dimitrios Sounas, Andrea Alu, Matteo Rinaldi This paper reports on the first demonstration of a highly-linear magnetic-free microwave Microelectromechanical Resonant Circulator simultaneously showing low insertion loss and large isolation at a microwave frequency (2.5 GHz).
SSW3: A Low-Power CMOS-MEMS Vibration Spectrum Analyzer Varun Subramaniam Kumar, Alireza Ramezany, Ajit Sharma, Siavash Pourkamali Currently, no low cost, low power, and compact vibration sensor solution exists that can provide frequency distribution data for measured vibrations. This work presents building blocks of a low-power, wide-band (DC-10kHz) mini-vibration spectrum analyzer with a resolution of 1mg.
SSW4: Towards Ka Band Acoustics: Lithium Niobate Asymmetrical Mode Piezoelectric MEMS Resonators Yansong Yang, Ruochen Lu, Tomas Manzaneque, Songbin Gong A new class of lithium niobate MEMS resonators that can potentially service 24 GHz bands for 5G wireless communications. The fabricated device has demonstrated an electromechanical coupling (kt2) of 1.8%, a high extracted mechanical quality factor (Q) of 400, and an fQ product of 0.96∙1013.
SSW5: Free-Space to Single-Mode Waveguide Coupling For Photonically Integrated Chip-Scale Spectroscopy Doug Bopp, Songbai Kang, Matthew Hummon, John Kitching, Sangsik Kim, Alexander Yulaev, Daron Westley, Kartik Srinivasan, Vladimir Aksyuk In an effort to build a compact and passively aligned wavelength reference, we employ grating-to-grating coupling enabling our devices to optically probe atoms with free space beams while retaining a chip-scale package with dielectric waveguides routing the light precisely.


WO1.1: Time and Frequency Dissemination

Moderator: Stefania Romisch

Paper Title Authors Executive Summary
WO111: Dissemination of Reference Signals for a Next Generation Radio Telescope Renier Siebrits, Johan Burger, Grant Adams, Etienne Bauermeister, Sias Malan, Romeo Gamatham, Thomas Abbott, Francois Kapp, Luyanda Buyana, Nontobeko Mnyandu, Siyabulela Tshongweni, Braam Otto, Carel Van der Merwe, Henno Kriel A fully integrated system for transmitting atomic clock signals over optical fibre, in a high branching ratio (64), directly to a radio telescope Digitiser Units is demonstrated to achieve ultra low jitter, sub picosecond phasing and sub nanosecond timing.
WO112: REFIMEVE+ : towards a wide optical fiber network for optical frequency standard dissemination Etienne Cantin, Olivier Lopez, Nicolas Quintin, Emilie Camisard, Giorgio Santarelli, Christian Chardonnet, Anne Amy-Klein, Paul-Eric Pottie We present a multi-branch long-haul coherent fiber links, serving as a node of an optical fiber network. We show reliable and robust operation over several months of operation, and successful knowledge transfer to industry to made the technology commercially available.
WO113: Two-branch fiber links for international clock networks Paul-Eric Pottie, Dan Xu, Anne Amy-Klein, Olivier Lopez, Etienne Cantin, Florian Frank, Frédéric Meynadier, Philip Tuckey, Nicolas Quintin We show a two-branch fiber links under operation for 5 weeks during a clock comparison campaign. We report an uptime of more than 90 % and a stability and accuracy at the level of 5×10-20 or below.
WO114: Portable Picosecond Synchronization Technique Based on Optical Free-space Time Transfer Jie Tian, Yongsheng Cheng, Nan Xie, Dong Hou A scheme of portable picosecond-level synchronization technique based on optical free-space time transfer is presented. The experimental results prove that this portable scheme is effective for high precision time transfer and synchronization over free-space link.
WO115: Effects of anisoplanatism on optical two-way time-frequency transfer William Swann, Martha Bodine, Laura Sinclair, Isaac Khader, Nathan Newbury, Jean-Daniel Deschenes Exploration of atmospheric anisoplanatism effect on optical time transfer reveals effective transfer under conditions of partial path reciprocity; furthermore an updated model explaining reciprocity, that includes beam tip/tilt, is presented.


WO1.2: Resonator Materials

Moderators: Sarah Bedair and Sid Ghosh

Paper Title Authors Executive Summary
WO121: Ferroelectric and Relaxor-Ferroelectric Thin Films for Piezoelectric MicroElectroMechanical Systems Nazanin Bassiri-Gharb, Evelyn Chin, Yulian Yao, Samuel Williams, Melissa Gallego, Grace Wei, Steven Brewer This presentation discusses advancements in the processing of ferroelectric, relaxor-ferroelectric and antiferroelectric thin films for applications in microelectromechanical sensors and resonators.
WO122: On fourth-order elastic constants of degenerately doped silicon resonators Ville Kaajakari, Takehiko Kishi, Toshio Nishimura Keys' theory on electronic effects in elastic constants is expanded to the fourth-order stiffness tensor. The expanded theory is necessary and sufficient to explain positive drive level dependency in heavily phosphorus doped silicon resonators.
WO123: Single Crystalline 4H-SiC Membrane Resonators Pen-Li Yu, Noah Opondo, Sen Dai, Boyang Jiang, Dallas Morisette, Sunil Bhave We report the first wafer-scale fabrication of semi-insulating, single-crystalline 4H-SiC membrane resonators by timed deep reactive ion etch (DRIE). 184 'μm deep trenches with 84.7osidewall angle are etched to form 16 'μm thick membranes with 500-1000 quality factors at ambient condition.
WO124: Switchable Bulk-Acoustic-Wave Transducers on a GaN-MMIC Platform Shreyas Shah, Dana Weinstein This abstract presents switchable thin-film bulk-acoustic resonators (FBARs) on a GaN-MMIC stack. The transduction efficiency of these resonators can be switched with a relative bias voltage applied to the two-dimensional electron gas at the AlGaN/GaN interface.
WO125: Effects of Bottom Electrode Topography in AlN Nano Plate Resonators on Quality Factor Zhenyun Qian We show that efficient piezoelectric transduction of a high frequency (~744 MHz) lateral-extensional mode of vibration and a quality factor as high as ~1300 can be achieved when a 70 nm thick platinum layer is employed as the interdigitated electrode underneath of a 200 nm thick AlN nano plate.


WO 1.3: Precision optical oscillators

Moderator: Rodolphe Le Targat

Paper Title Authors Executive Summary
WO131: Optical lattice clocks with thermal or quantum degenerate atoms Jun Ye  
WO132: Precision visible frequency comb in the visible with sub-mHz resolution Antoine Rolland, Peng Li, Marco Cassinerio, Jie Jiang, Martin Fermann We report a highly coherent visible frequency comb, from a doubled 1550 nm Er fiber laser. We demonstrate the coherence of the comb through a 698/1064 nm frequency ratio measurement. The fractional residual instability is lower than 6×10-18 at 1 s and reaches 3×10-20 after 1000 s of averaging.
WO133: Spectral Purity Transfer for High Performance Strontium Lattice Clocks Michele Giunta, Wolfgang Hänsel, Matthias Lezius, Marc Fischer, Ronald Holzwarth, Erik Benkler, Dan Matei, Thomas Legero, Uwe Sterr We investigate the spectral purity transfer of highly stable lasers from 194 THz to 429 THz using optical frequency combs. In particular, we compare the performance of a fully-stabilized ultra-low noise comb and a free-running transfer oscillator frequency comb.
WO134: Development of a cryogenic silicon cavity stabilized laser Yann Kersalé, Baptiste Marechal, Santerelli Falzon Tetsing Talla, Jacques Millo, Cyrus Rocher, Pierre-Yves Bourgeois, Gwenhaël Goavec-Mérou, Clément Lacroûte, Enrico Rubiola We present the development status of a cavity stabilized laser at 1550 nm. The expected thermal noise limit of the silicon Fabry-Pérot cavity is 3x10^-17 in terms of fractional frequency instability at 17 K.
We also discuss the environment induced limitations and the digital servo performances.
WO135: A cryogenic high-finesse optical cavity to improve the stability of Yb optical lattice clocks Daniele Nicolodi, William F. McGrew, Robert J. Fasano , Xiaogang Zhang, Kyle P. Beloy , Marco Schioppo, Andrew D. Ludlow We report on the implementation of a high-finesse optical cavity operating at 4 K allowing potential for for low 10-17laser fractional frequency stability. Original solutions for minimizing acceleration noise, residual amplitude modulation, and other technical noise will be presented.


Poster Session I: Analysis of Resonant Devices

Moderator: Jan H. Kuypers

Paper Title Authors Executive Summary
WP01: Aspect Ratio Influence on Anchor Loss Using Rapid Analytical FEA Technique Ryan Rudy, Sarah Bedair, Jonathan Puder, Ronald Polcawich, Jeffrey Pulskamp Aspect ratio and its effect on quality factor and coupling factor in length extensional resonators is analyzed through a rapid analytical/3D-FEA hybrid approach. Experimental data is compared highlighting specific aspect ratios which mitigate anchor loss.
WP02: Orientation-Dependence of Anchor Damping and Thermal Expansion Coefficients in Silicon MEMS Resonators Janna Rodriguez, Christopher Watson, Grant Glaze, Gabrielle Vukasin, Ian Flader, Yunhan Chen, Chae Anh, Thomas Kenny These experiments enable the identification of the contributions of TED, pressure damping and anchor damping. This approach has revealed some unexpected factors that can impact anchor damping, and detects parts of the orientation dependence of the coefficient of thermal expansion in silicon
WP03: Achieving the Intrinsic Limit of Quality Factor in VHF Extensional-Mode Block Resonators Hakhamanesh Mansoorzare, Sina Moradian, Sarah Shahraini, Jonathan Gonzales, Reza Abdolvand In this work, through altering the substrate regions around the resonators, we demonstrate that it is possible to push the most dominant sources of extrinsic loss in high-frequency thin film piezoelectric (TPoS) MEMS resonator to levels that they no longer limit the overall Q.
WP04: An Analytical Formulation of the Radio-Frequency Response of Piezoelectric Contour-Mode MEMS Resonators Verified by Measurements Johannes Stegner, Sebastian Gropp, Dmitry Podoskin, Uwe Stehr, Martin Hoffmann, Matthias Hein An analytical formulation of MEMS resonators is presented that has not been published before. The mechanical wave equation is solved for the stress wave in a contour-mode resonator. The resulting equivalent-circuit model coincides with measurement results and verifies its correctness.
WP05: Frequency stability of 3D encapsulated VHF MEMS resonator Jinling Yang, Fengxiang Wang, Quan Yuan, Xiao Kan, Zeji Chen, Fuhua Yang Frequency stability of 3D encapsulated VHF MEMS resonator was studied for both long-term operation and temperature cycling with negating capacitive compensation technique developed for eliminating the parasitic effect. High stability of the encapsulated resonator was demonstrated.
WP06: Experimental Mapping of the Operational Regimes of Phononic Frequency Combs Adarsh Ganesan, Ashwin Seshia Using an exemplar resonator device, this paper probes the emergence of new regimes of phononic frequency combs owing to the interplay between '(𝑵 + 𝟏)-wave mixing' and pumped '(𝑵 + 𝟏)-wave mixing'
WP07: Frequency-temperature relations of novel cuts of quartz crystals for resonator applications  Ji Wang, Liangmeng Zhang, Shaoyun Wang, Longtao Xie, Tingfeng Ma, Jianke Du, Yook-Kong Yong We analyzed the thickness-shear vibrations of quartz crystal plates to confirm the superior frequency-temperature relations with the theory of incremental thermal field and Mindlin plate equations and presenting comparisons with known AT- and SC-cut resonators.
WP08: A Comprehensive Model for Graphene Resonator Frequency Tuning via Electrostatic Gating Philip Feng, Tengda Mei, Jaesung Lee, Yuehang Xu We report on a comprehensive frequency tuning model of graphene nanoelectromechanical (NEMS) resonators via electrostatic forces induced by gate voltage. The model provides explicit mathematical expressions, and we find three different tuning behaviors based on built-in strain level.
WP09: Advanced ion beam technology to extremely precise 0.1nm surface trimming Sebastian Gatz, Monika Fritzsche, Dirk Rost, Jens Landrock, Anja Banholzer The paper discusses Ion Beam Technology as an alternative technology to trim dielectric and metal layers in the 0.1nm range for applications as Surface Acoustic Wave (SAW) and Bulk Acoustic Wave (BAW) filters.
PF01: Temperature Coefficient of Frequency in Silicon-Based Cross-Sectional Quasi Lame Mode Resonators Sarah Shahraini, Hedy Fatemi, Reza Abdolvand Cross-sectional quasi-lame modes (CQLMs) are demonstrated in thin-film piezoelectric-on-silicon (TPoS) resonators. The temperature coefficient of frequency is predicted using a developed model in COMSOL. A turnover temperature of above 100 C is measured for <100> aligned CQLM resonator.
PF02: Towards Ka Band Acoustics: Lithium Niobate Asymmetrical Mode Piezoelectric MEMS Resonators Yansong Yang, Ruochen Lu, Tomas Manzaneque, Songbin Gong A new class of lithium niobate MEMS resonators that can potentially service 24 GHz bands for 5G wireless communications. The fabricated device has demonstrated an electromechanical coupling (kt2) of 1.8%, a high extracted mechanical quality factor (Q) of 400, and an f
PF03: High-Cx/Co Hollow Disk Resonators Alper Ozgurluk, Yafei Li, Clark T.-C Nguyen Mass and stiffness reduction by hollowing out a capacitive-gap transduced radial mode disk resonator while keeping resonance frequency and transduction area the same has yielded a measured electromechanical coupling strength (Cx/Co) of 0.56% at 123 MHz.
PF04: 2.5 GHz Highly-Linear Magnetic-Free Microelectromechanical Resonant Circulator Yao Yu, Flavius Pop, Giuseppe Michetti, Piotr Kulik, Michele Pirro, Ahmed Kord, Dimitrios Sounas, Andrea Alu, Matteo Rinaldi This paper reports on the first demonstration of a highly-linear magnetic-free microwave Microelectromechanical Resonant Circulator simultaneously showing low insertion loss and large isolation at a microwave frequency (2.5 GHz).


Poster Session I: Oscillators, Synthesizers, and Circuits Techniques

Moderator: Archita Hati

Paper Title Authors Executive Summary
WP10: A Low Jitter Monolithic MEMS Thin Film SAW Oscillator in 0.13 &[mu]m CMOS Ahmad El-Hemeily, Sameh A. Ibrahim, Mohamed Atef, Ali Fawzy, Ayman Ahmed, Eloi Marigo Ferrer, Mohanraj Soundara Pandian, Arjun Kumar Kantimahanti A fully-integrated solution for reference oscillators using thin film SAW CMOS technology is presented and validated through measurements. The SAW oscillator has an excellent phase noise performance, integrated phase jitter from 12 kHz to 20 MHz reaches 160 fs and the best area utilization.
WP11: Quasi-zero-stiffness Vibration Isolator for Ultra-stable Optical Cavity of Atomic Clock Lei Liu, KeDa He, Guanjun Xu This paper proposes a quasi-zero-stiffness vibration isolator design method. Moreover, the simulation is carried out to verify the designed vibration isolator. The Simulation results illustrate that the isolation performance is better than 14 dB in the range of 1 Hz to 10 Hz.
WP12:Optomechanical coupling in a quartz crystal resonator for cryogenic clocks Jérémy Bon, Kevin Rosenziveig, Philippe Abbé, Cyrus Rocher, Serge Galliou, Leonhard Neuhaus, Samuel Deléglise, Tristant Briant, Pierre-François Cohadon From our knowledge, this is the first time that a quartz acoustic cavity is intended to be used as an optical cavity as well. The demonstration is based on data from usual plano-convex quartz resonators, regarding their geometrical parameters as well as their behavior at low temperature.
WP13: An Ultra-Low-Power Third-Order Frequency-to-Digital Converter for FM MEMS Gyroscope Yang Zhao, Zhiqiang Wu, Guoming Xia, Qin Shi, Yu Wang, Anping Qiu, Haiying Wang, Jianfeng Du This paper proposes a third-order noise shaping frequency-to-digital converter for FM gyroscope. It achieves 8μHz or 10dph resolution in 10Hz bandwidth with only 200kHz reference clock frequency and consumes only 1.26μW power consumption.
WP14: A Low-Jitter Technique of Frequency Multiplication Using Quartz Crystal Array Zhiqiang Zhou, Yuan Liu, Shaoshuang Su, Xiaojiang Liang and Ping Wang A novel technique for frequency multiplication provides higher frequency clock output using the crystal array from the crystal filters. This paper presents the analysis and design in both crystal array arrangement. The low-jitter and high frequency stability characteristics is discussed.
WP15:Realization of Voltage Controlled Temperature Compensated Crystal Oscillator with Single Varactor xianhe huang, Fusheng Peng, Yimei Li, Jianguo Hu The implementation of a VCTCXO with a single varactor is presented. At around the center frequency of the VCTCXO, its frequency drift affected by temperature was suppressed effectively.
PF05:Commercial Crystal and MEMS Oscillators characterized at Deep-Cryogenic Temperatures Harald Homulle, Edoardo Charbon In this work we present for the first time the operation of commercial crystal and MEMS devices operating at deep-cryogenic temperatures. These devices were characterized to complement a cryogenic FPGA system and generate clock signals of either 50 or 100 MHz to operate the FPGA.
WP16: Compact High-Precision Analog Temperature Controller for MEMS Inertial Sensors Arif Mustafazade, Ashwin A. Seshia A compact analog temperature controller for MEMS inertial sensors with a long-term stability of ±250 &[micro]&[deg]K p-p (over 12 hrs). The fully analog design makes it suitable for noise sensitive applications. A linear circuit technique is employed to minimize power dissipation in the controller to < 5mW.
WP17: A Direct Feedback Oscillator Topology Employing Weakly Coupled Resonators for Gain Control Chun Zhao, Milind Pandit, Guillermo Sobreviela, Arif Mustafazade, Sijun Du, Xudong Zou, Ashwin Seshia This paper presents a new class of oscillator topology features only one constant gain transimpedance amplifier in the loop. This new oscillator topology can potentially enable future low noise and low-power integrated oscillator design without an external electronic gain control.
WP18: α Factor Measurement Using Laser Dynamics Yanguang Yu, Yuxi Ruan, Bin Liu, Jiangtao Xi, Qinghua Guo, Jun Tong This paper presents a new method for measuring α by the dynamics of a semiconductor laser. Staring from the well-known Lang-Kobayashi equations, we investigated the transient behavior of an SL induced by external optical feedback, and the relationship between SL's RO frequency and α.
WP19: A self-mixing laser diode for profile measurement Yanguang Yu, Han Wang, Jiangtao Xi, Qinghua Guo, Jun Tong This paper presents an self-mixing laser diode (SMLD) for profile measurement. The LD is modulated by a triangular waveform injection current. The reflection light contains the target's profile information. A new algorithm is developed to retrieve the profile from the signal.
PF06:Implementation of Multi-Step Look-Ahead Sigma-Delta Modulators Using IC Technology Charis Basetas, Nikos Temenos, Paul Peter Sotiriadis The first hardware implementation of Multi-Step Look-Ahead Sigma-Delta Modulators (MSLA SDMs) in IC technology is presented and hardware optimization techniques are discussed. They exhibit 10-12 dB higher signal-to-noise-and distortion ratio (SNDR) than conventional single-bit SDMs
PF07: Field-deployable Photonic Microwave Synthesizer Michele Giunta, Wolfgang Hänsel, Maurice Lessing, Matthias Lezius, Marc Fischer, Ronald Holzwarth, Xiaopeng Xie, Romain Bouchand, Daniele Nicolodi, Yann Le Coq, Pierre-Alaine Tremblin, Giorgio Santarelli, Shubo Datta, Abbay Joshi We report on the development of a transportable photonic microwave synthesizer comprising an ultra-stable laser and a compact ultra-low-noise frequency comb used for dividing the spectral purity from optical to radio frequencies.
PF08: Low phase noise cryogenic amplifiers and oscillators based on superconducting resonators David CHAUDY, Olivier Llopis, Jean-Michel Hode, Bruno Marcilhac, Yves Lemaitre, Olivier d'Allivy Kelly A cryogenic low phase noise amplifier and an high Q superconductor resonator at 1GHz have been designed and realized. A good agreement between the measured and simulated data at 80K is observed. An all cryogenic oscillator has also been designed with the same devices. But is still under test


Poster Session I: Microwave Clocks and Applications

Moderator: Elizabeth Donley

Paper Title Authors Executive Summary
WP20: Preliminary Evaluation of NRC-FCs2 Fountain Clock at the National Research Council Canada Scott Beattie, Bin Jian, A. John Alcock, Marina Gertsvolf, Rich Hendricks, Krzysztof Szymaniec, Kurt Gibble At the National Research Council Canada we are currently performing the first accuracy evaluation of our newly developed caesium fountain clock, NRC-FCs2. We will discuss the current status of the evaluation.
WP21: Using a low phase noise H-maser as a local oscillator for Rb discriminator Michael Aleynikov, Alexander Boyko, Igor Blinov, Sergey Donchenko One of the problems in pulsed-operated atomic clocks is a phase noise of local oscillator (LO). The solution via application of special designed H-maser as LO is described. This way is quite simple because it requires neither cryogenic microwave oscillators nor complicated optical systems.
WP22: The study of Ramsey and Rabi frequency pulling shift ruan jun, shi junru, guan yong, wang xinliang, liu dandan, zhang hui, bai yang, yu fengxiang, liu hao, yang fan, zhang shougang 1.By solving time-evolution operator&rsquo;s differential equation, we derive Ramsey and Rabi frequency pulling shift. 2.In order to measure this frequency shift, we magnify this frequency shift by feeding in two microwaves to selection cavity and increasing Ramsey cavity's microwave pulse area.
WP23: A portable cold 87Rb atomic clock with frequency instability at one day in the 10-15 range Franklin Ascarrunz, Yaroslav Dudin, Maria Delgado Aramburo, Leonardo Ascarrunz, Joshua Savory, Alessandro Banducci, Steven Jefferts We present a new class of small portable laser cooled atomic clock. The clock has a short term frequency stability characterized by 8 X 10-13/&[radic]τ and a long term stability < 3 X 10-15. The portable clock is about the size of a desktop computer (22x37x32 cm) and weighs 28kg.
WP24: Miniaturized and low power mercury microwave ion clock Nan Yu, Gurpreet Gulati, Sang Chung, Thanh Le, John Prestage, Lin Yi, Robert Tjoelker, Chris Holland Our paper reports the development of a miniature ion trap package with field emitter array in a hybrid linear RF trap configuration, a key part of a micro mercury trapped ion clock.
WP25: Isotopically Pure Silcon 28 Whispering Gallery Mode Resonators: A Host for Narrow Linewidth Spin Ensembles Michael Tobar, Jeremy Bourhill, Maxim Goryachev, Daniel Creedon, Brett Johnson, David Jamieson Single crystal isotopically pure Si28 WG mode resonators have been realized at microwave frequencies. They can exhibit Q-factors above 10^6 and can contain narrow linewidth spin ensembles of less than 7 KHz. ESR spectroscopy can detect spin concentrations of less than 10 parts per trillion.
WP26: Frequency Response of a Close-Loop Bell-Bloom Magnetometer Hong Guo, Rui Zhang, Bo Pang, Wenhao Li, Yucheng Yang, Jingbiao Chen, Xiang Peng The dependence of the frequency response of a close-loop Bell-Bloom magnetometer on its various experimental parameters is studied, and the experimental data show good agreement with the simulation results.
WP27: Investigation of Rabi Rsonance for Measuring Microwave Magnetic Field Fuyu Sun, Xiaochi Liu, Zhiyuan Jiang, Jifeng Qu, Dong Hou, Qingsong Bai, Xianhe Huang We have presented a technique for measuring unknown microwave fields based on Rabi resonances induced by the interaction of atoms with a phase modulated microwave field. The single-peak feature of the measurement model makes the technique a valuable tool for simple and fast field measurement.
WP28: Progress of the Atomic Fountain Clock KRISS-F1 Taeg Yong Kwon, Sang-Bum Lee, Sang Eon Park, Myoung-Sun Heo, Hyun-Gue Hong, Sangmin Lee, Kurt Gibble, John Hartnett We present the current status of the atomic fountain clock KRISS-F1 under development at KRISS. The short-term stability measured with the CSO reaches 3.2&[times]10-14at an averaging time of 1 s. The systematic uncertainty of the fountain is expected to reach low 10-16 level.
WP29: Atomic Gravimeter based on Atom Interferometry Being Developed at KRISS Taeg Yong Kwon, Sang-Bum Lee, Sang Eon Park, Myoung-Sun Heo, Hyun-Gue Hong We present the current status of an atomic gravimeter being developed at KRISS for precise absolute gravity measurement. The gravimeter is based on atom interferometry with laser cooled 87Rb atoms. The short-term stability of the gravity measurement is 1.6&[times]10-8 at 1 s average time.
PF09: Off-resonant Light Shift in CPT Ramsey Spectroscopy of Clock Transitions James Pollock, Moshe Shuker, Xiaochi Liu, John Kitching, Elizabeth Donley, Valera Yudin, M. Yu. Basalaev, Alexey Taichenachev The off-resonant light shift for CPT Ramsey spectroscopy is investigated both theoretically and experimentally. We show that the shift of the central Ramsey fringe depends on the intensity ratio of the two CPT light fields, but only depends weakly on the total laser intensity.
PF10: Progress Towards a Cadimium Ion Microwave Clock based on Sympathetic Cooling JIANWEI ZHANG, YANI ZUO, JIZE HAN, LIJUN WANG The precision of 113Cd+ microwave clock is mainly determined by the measurement accuracy of hyperfine splitting. To reduce the SODFS, we use sympathetic cooling by 24Mg+. By comparing the experiment results with MD simulation, we discuss the efficiency and influence of sympathetic cooling.
PF11:Inhomogeneous Light-Shift in Helium Magnetometer Sheng Li, Haidong Wang, Zaisheng Lin, Xiang Peng, Jingbiao Chen, Hong Guo We present a study on inhomogeneous light-shift caused by light-intensity gradients in $^4$He atomic vapor cell of Helium magnetometer. Light shifts in different locations over the cell dimensions are measured and generally show a diminishing character along the traveling path of light beam.
PF12: A Portable Microwave Clock Using Laser-Cooled Trapped 171YbIons Sean Mulholland, Sean Donnellan, Geoffrey Barwood, David Gentle, Guilong Huang, Hugh Klein, Pravin Patel, Greg Walsh, Patrick Baird, Patrick Gill We report on progress in the development of a compact microwave frequency standard, designed to fit in a 19-inch rack enclosure, incorporating laser-cooling of 171Yb+.


Poster Session I: Sensors and Transducers

Moderator: Sid Tallur

Paper Title Authors Executive Summary
WP30: Thermal Piezoresistive Resonant Mass Balance Implemented in a Standard CMOS Process Amin Abbasalipour, Varun Kumar, Siavash Pourkamali This work presents implementation of electro-thermally actuated MEMS resonators in a standard CMOS process via addition of a few mask-less post-processing steps.
WP31: Coupled Nonlinear MEMS Resonators for Sensing Milind Pandit, Chun Zhao, Guillermo Sobreviela, Arif Mustafazade, Ashwin Seshia This work describes weakly coupled resonators operating at their nonlinear bifurcation points. The noise floor and the sensitivity of the amplitude ratio to input stiffness perturbations are experimentally determined for the two bifurcation points and compared to their linear counterpart.
WP32: Increased Output-Pressure PMUTs with a Sloped Profile Fabricated via Surface Micromachining Guo-Lun Luo, Qi Wang, Yuri Kusano, David Horsley This study implements a novel high-efficiency AlN PMUT by the surface micromachined process with high fill-factor. The design of PMUT with sloped diaphragm can be approached to have an enhanced displacement with the higher electromechanical coupling coefficient.
WP33: A Proposal for Absolute Inertial Imaging using Two Mechanical Modes Adarsh Ganesan, Ashwin Seshia This paper presents an approach towards inertial imaging of physical perturbations of a mechanical resonator with absolute resolution, using two mechanical modes.
WP34:Nanomechanical Disk Resonator-on-Membrane with Pico-Meter Deflection Resolution VAHID QARADAGHI, Alireza Ramezani, Mohammad Mahdavi, Siavash Pourkamali This paper reports on the fabrication of nanomechanocal disk resonators on micro-membranes and characterization of their resonance frequency shift due to air-pressure induced membrane deflection.
WP35: A Resonant MEMS Accelerometer Utilizing AC Polarization Chun Zhao, Guillermo Sobreviela, Milind Pandit, Arif Mustafazade, Sijun Du, Xudong Zou, Ashwin Seshia In this paper, we present a resonant MEMS accelerometer down-converted to the oscillation frequency to 10kHz. With this approach, when compared to DC polarized configuration, the improvement for stability and noise floor is 1.7 times and 2 times, respectively.
WP36: SAW sensor with HFM reflectors Victor Plessky, Aleksey Shimko, You Jen Cho, Rimantas Miskinis, Dmitrij Smirnov The SAW sensor exploiting Hyperbolically Frequency Modulated (HFM) signals designed, manufactured and measured.
WP37: Retrieve the material related parameters from a self-mixing signal using wavelet transform Yanguang Yu, Fei Xia, Yuxi Ruan, Jiangtao Xi, Qinghua Guo, Jun Tong This paper presents a method for retrieving material related parameters using a self-mixing interferometric (SMI) configuration. By applying the wavelet transform onto the SMI signals, the vibration information for calculating material related parameters can be retrieved.
PF13: Micro-Resonator-on-Membrane For Real-time Biosensing Mohammad Mahdavi, Honglei Wang, Amin Abbasalipour, Walter Hu, Siavash Pourkamali Micro-Resonator-on-Membrane (MRoM) is presented as new highly sensitive balance for real-time biosensing. An MRoM is composed of a rectangular resonator separated by a thin SiO2 membrane from backside cavity which houses biologic solution. The MRoM exhibits a sensitivity of -89 Hz.cm2/ng.
PF14: A 200-nm-gap Titanium Nitride Composite CMOS-MEMS CMUT for Biomedical Ultrasounds Sheng-Shian Li, Tzu-Hsuan Hsu A CMUT is presented with < 200 nm gap based on a tailored TiN-C CMOS-MEMS platform. Single-channel water-immersed ultrasound receiver CMUT with 20 dB amplifier is characterized using a pulser and an unfocused probe at 12 mm atop, exhibiting a sensitivity of 2.28 mV/kPa with only 40 V of dc bias.
PF15: MEMS Surface Coating Condition Monitoring via Nonlinear Tapping of Resoswitches Wei-Chang Li, Shi-Chuan Lu, Wun-Ruei Du A MEMS resoswitch-enabled surface coating condition monitoring device is demonstrated as a proof of concept that successfully identifies the existence of molecular coating on the surfaces. Such devices can in situ monitor, e.g., anti-stiction coated surfaces of MEMS motion sensors.
PF16: Frequency Doubling in Wirelessly Actuated Multiferroic MEMS Cantilevers Sidhant Tiwari, Max Ho, Robert Candler Nonlinearity in multiferroic coupling is tested using MEMS cantilevers. With the nonlinearity, it's possible to drive the devices wirelessly with magnetic fields at half the cantilever resonance frequency. This may be a route for low noise measurement of wireless signals with multiferroics.


Poster Session I: Timekeeping, Time & Frequency Transfer, GNSS Applications

Moderator: Aimin Zhang

Paper Title Authors Executive Summary
WP38: Satellite-induced Code Bias Variation effects in BDS time transfer qin weijin, ge yulong, wu wenjun, yang xuhai The Workgroup_GNSS_CCTF2017_CR report pointed that the problem of elevation-dependent biases is already documented and should be accounted for in time transfer use. This paper analysed the effects of CBV on code-based BDS time transfer.
WP39: BDS PPP Time Transfer at NTSC Jihai Zhang With the developing of global navigation system, the high quality positioning, navigation and time (PVT) service are gradually provided by BeiDou navigation system (BDS) in China. In this paper, the BDS Precise Point Positioning (PPP) time transfer is studied.
WP40: The test on CAPS experimental system time transfer wu feng From 2010 to 2017, CAPS developed from the verification system to the experimental system. The results are as follow: The uncertainty of time transfer is 2.87ns in Xi'An, and the uncertainty of time transfer is 3.81ns in Beijing .
WP41: Time Transfer and Calibration in EMI Sensitive Environment Romeo Gamatham, Renier Siebrits, Johan Burger, Grant Adams, Thomas Abbott, Francois Kapp, Siyabulela Tshongweni, Braam Otto, Carel Van der Merwe, Nontobeko Mnyandu, Chris Matthee There are unique challenges involved with precision time transfer in environments where ultra-low interference (below -200dBm/Hz) are required near highly sensitive RF receivers. A specialized travelling receiver under development which is optically isolated is presented.
WP42: Identifying metrics and their attributes for ensuring the integrity of GPS signals Bijunath Patla, Neil Ashby, Stefania Romisch The needfor GNSS devices to be more resistant to any vulnerabilitiesis a requirement for robust timing applications. We identify a set of metrics and explore theirinterdependent relationships in an effort to converge on anddiscriminate between the most common threats.
WP43: A method of obtaining high precision propagation delay for BPL timing signal Yun Li, Yu Hua, Baorong Yan, Wei Guo Based on the analysis of relationship among the propagation delay of different users received signal .A method of obtaining high precision propagation delay is proposed; the method is verified by the actual measurement data. The result show achieved accuracies of better than 100ns .
WP44: Research of digital satellite TV differential timing method shanhe wang, yu xiang, yu hua, jun ju, weicheng xue High precision time transfer method based on the digital satellite TV signal had been reserached in 2008 by NTSC. The theoretical derivation and experiments show that timing precision of digital satellite TV differential timing method is higher than 10ns.
WP45: The influence of solar flare on low frequency time-code timing signal Wang Xin, Li Xiaohui, Feng Ping, Li Wei 5 typical solar flare events were selected to analyze the field strength and phase of low frequency timing signal during solar flare,we can see that the burst of X ray flux above C7 level has significant influence on the field strength and phase of the low frequency continuous wave signal.
PF17: Investigation into a GPS time pulse radiator for testing time-stamp accuracy of a radio telescope Zwivhuya Ramudzuli, Thomas David Abbott An independent, system to verify the end-to-end time stamping accuracy of a radio telescope. It radiates a modulated RF signal. The system is simple and so less prone to accounting errors. It discovered a large offset on MeerKAT.
WP46: High performance Timing synchronisation for industrial logic level control utilising low cost miniature single board computer with EMC compliance Grant Adams, Renier Siebrits, Johan Burger, Etienne Bauermeister, Sias Malan, Francois Kapp, Luyanda Buyana, Nontobeko Mnyandu, Siyabulela Tshongweni, Braam Otto, Carel Van der Merwe, Marc Welz, Robin van Wyk The integration of time transfer and control on a miniature single board computer system is presented. allowing sub 1 microseconds level hardware time stamping control. The system is based on low cost COTS hardware. External time referencing can be supplied via PTP or via a PPS signal.
PF18: ACES-Pharao test of the gravitational redshift : Refined esimation of the expected sensitivity Etienne SAVALLE, Christine Guerlin, Frédéric Meynadier, Pacôme Delva, Christophe Le Poncin-Lafitte, Philippe Laurent, Peter Wolf We estimate a statistical uncertainty in the low 10^-6 for the gravitational redshift test with ACES-Pharao mission specifications.Then, using highly deteriorated ISS orbit determination, we find that orbit errors of up to 1km would still allow to reach this uncertainty.
PF19: First Field Trial of the Frequency Transfer System with Passive Stabilization Scheme Song Yu, Chenxia Liu, Tianwei Jiang, Ruihuan Wu, Dongxing Wang, Jingxi Liang, Xing Chen, Yaojun Qiao we reports on a stable radio frequency (RF) dissemination system via optical fiber. After transmitted over 80 km commercial telecom fiber link, the measured fractional frequency instability (Allan deviation) of 2.4 GHz RF signal is 7.9&[times]10 -17 for 10000 s averaging time.
PF20: Nonlinear Interaction between Neighboring Data Channels and a Frequency Signal in a Commercial Optical Fiber Communication System Patrick Sykes, Chaoran Tu, Curtis Menyuk We investigate the stability of a frequency signal due to the effect of cross-phase modulation between neighboring data channels. Research networks use a data channel to experiment frequency transfer. We investigate the frequency signal placed in the interstice of two data channels.


Poster Session I: Optical frequency standards and combs

Moderator: David Leibrandt

Paper Title Authors Executive Summary
WP47: Towards a quantum logic 27Al+ ion optical clock Ke Deng, Hongli Liu, Zetian Xu, Huang Che, Wenhao Yuan, Jie Zhang, Zehuang Lu A quantum logic 27Al+ ion optical clock is under development at Huazhong University of Science and Technology. 25Mg+ ion is chosen as the logic ion. Three experimental issues are discussed in the paper.
WP48: Preliminary progress in the development of an operational calcium thermal beam clock at the U. S. Naval Observatory Bryan Hemingway, Jennifer Taylor, Thomas Swanson, Steven Peil We will present the progress on neutral calcium 40 optical clock development at the United States Naval Observatory.
WP49: Microwave Frequency Generation Using a Non-Octave-Spanning Optical Frequency Comb James Cahill, Weimin Zhou, Curtis Menyuk We evaluate the challenges in realizing ultra-low-phase-noise microwave generation with a self-stabilized optical frequency comb that does not need to be octave spanning.
WP50: Design and characterization of ion traps for 27Al+ quantum-logic clocks Aaron Hankin, Ethan Clements, Samuel Brewer, Jwo-Sy Chen, David Hume, Chin-wen Chou, David Wineland, David Leibrandt We characterize four styles of wheel-shaped, differentially-driven linear Paul traps for the 27Al+ optical clock and show how improved geometric symmetry will improve clock accuracy by reducing time-dilation shifts.
WP51: Supercontinuum generation of highly nonlinear fibers pumped by 1.56um laser solitons Songtao Fan, Yanyan Zhang, Lulu Yan, Wenge Guo, Xiaofei Zhang, Shougang Zhang, Haifeng Jiang We report on a supercontinuum generation in four types of highly nonlinear fibers (HNLFs) pumped by 1.56-μm laser solitons. Experimental results match the former supercontinuum evolution and provide guidelines for choosing and using HNLFs for erbium frequency combs and their applications.
WP52: Precise control of amplitude to phase noise conversion by biasing photo-detector for microwave generation with ultra-fast optical pulses Tang Li, Junchao Huang, Lingke Wang, Yifei Duan, Liang Liu We demonstrate a precise control of amplitude to phase noise conversion (APC) by biasing photodetector in the detection of ultra-fast optical pulses. This approach allows phtodetectors to operate at 'null APC' points in a wide range of optical energy.
WP53: All polarization-maintaining fiber laser for femtosecond pulse generation at NTSC Pan Zhang, Yanyan Zhang, Lulu Yan, Bingjie Rao, Wenyu Zhao, Shougang Zhang, Haifeng Jiang the laser directly generates output power of 3.15 W at repetition rate of 87.7 MHz, corresponding to the pulse energy of 37 nJ. The center wavelength is 1585 nm with the spectral bandwidth of 23 nm at the maximum output power.
WP54: Realization of Closed-Loop Operation of Optical Lattice Clock Based on 87Sr at NTSC Hong Chang, Yebing Wang, Dehuan Kong, Mojuan Yin, Qinfang Xu, Benquan Lu, Yang Guo, Jie Ren We report the optical lattice clock based on 87Sr in National Time Service Center of China. A fractional frequency instability of 87Sr optical lattice clock is down to 5.7&[times]10-17 for an averaging time of 3000 s. The Allan deviation is found to be 5&[times]10-15/τ 1/2.
WP55: Route to a Portable Optical Clock Yeshpal SINGH, Sruthi Viswam, Jonathan Bass, Marco Menchetti, Qasim Obaid, Jonathan Jones, David Morris, Peter Molony, Markus Gellesch, Matthew Aldous, Kai Bongs Novel atom Source and Compact Frequency Stabilising Unit
WP56: Direct Selection and Amplification of An Optical Frequency Comb via Injection Locking for Second Cooling Laser of Strontium Optical Clock Hong Chang, Qinfang Xu, Mojuan Yin, Dehuan Kong, Yebing Wang, Benquan Lu, Yang Guo We have realized direct selection and amplification of an optical frequency comb via injection locking for second cooling laser of strontium optical clock. Despite the low injection of individual comb mode, a single comb line could be filtered and amplified to reach 11 mW with narrow linewidth.
PF21: Detailed Characteristics and Cavity Stabilization of Dual-wavelength Good-bad Cavity Active Optical Clock Duo Pan, Tiantian Shi, Jingbiao Chen We realize a dual-wavelength cavity active optical clock and measure the characteristics of the output signals. We build two independent systems and lock their cavity length. Heterodyning between the two systems are conducted to obtain the frequency stability of the active optical clock.
PF22: Spectral Purity Transfer for High Performance Strontium Lattice Clocks Michele Giunta, Wolfgang Hänsel, Matthias Lezius, Marc Fischer, Ronald Holzwarth, Erik Benkler, Dan Matei, Thomas Legero, Uwe Sterr We investigate the spectral purity transfer of highly stable lasers from 194 THz to 429 THz using optical frequency combs. In particular, we compare the performance of a fully-stabilized ultra-low noise comb and a free-running transfer oscillator frequency comb.
PF23: Silicon cavity at 4 Kelvin with thermal noise limited performance John Robinson, Eric Oelker, Wei Zhang, Lindsay Sonderhouse, Will Milner, John Hall, Christian Sanner, Jun Ye, Dan Matei, Thomas Legero, Fritz Riehle, Uwe Sterr We present, for the first time, the thermal noise limited performance of a cryogenic ultrastable silicon optical cavity operated at 4 K. A three-cornered comparison shows that the 4 K system is largely limited by a flicker frequency floor near 7x10-17 for averaging times from 5 to 30 seconds.
PF24: Frequency comparison of two ytterbium optical lattice clocks at NIST with low 10-18 level uncertainty Xiaogang Zhang, William McGrew, Stefan Schaeffer, Kyle Beloy, Robert Fasano, Daniele Nicolodi, Roger Brown, Richard Fox, Andrew Ludlow We have evaluated systematic shifts of the NIST ytterbium optical lattice clock at the 10-18 level. We compared the frequency of two distinct ytterbium optical lattice clocks with low 10-18 uncertainty and frequency agreement at the same level, supporting the evaluated frequency uncertainty.