Tuesday, May 22

Plenary I: Richard Muller

Paper Title Authors
PL1: The Physics of Time: Why does it flow?

Richard Muller

Abstract: We know much about time, about its variability with velocity and gravity. Einstein took time to be the fourth dimension. But time is different. We can stand still in space (given any coordinate system) but not in time. Why? What is the meaning of “now”—that ephemeral concept whose meaning changes every moment? I don’t know where you are, but I do know something about you: you are reading the word “now” right now! I will present a new theory for the flow of time, one that links it to the creation of new space through the expansion of the Universe. The old postulated connection between entropy and the arrow of time will be discredited as an untestable theory—or, more precisely, as a theory that has failed multiple tests. Remarkably, the new theory I will present is testable. Events that create new space, such as the collision of two black holes that led to the observation of gravitational waves, create new space at the site of the collision, and according to the theory, they should create a potentially observable level of new time. 

GNSS-Degraded Environments

Robert Lutwak

Paper Title Authors Executive Summary
SST1: Time Synchronization over a Free-Space Optical Communication Channel Isaac Khader, Hugo Bergeron, Laura Sinclair, William Swann, Nathan Newbury, Jean-Daniel Deschênes We demonstrate real-time synchronization between two sites over a turbulent air path of 4 km using a free space optical digital communication channel with sub-3-ps time deviation below the synchronization bandwidth. Over an 8-hour period the peak-to-peak wander is 16 ps.
SST2: An Improved Cs Fountain Primary Frequency Standard For Commercial Realisations Richard Hendricks, Krzysztof Szymaniec, Filip Ozimek, Scott Beattie, Bin Jian, Piotr Dunst, Bartlomiej Nagorny, Jerzy Nawrocki, Krzysztof Turza, Kurt Gibble We have designed and built a number of state-of-the-art Cs fountains that have been sent to partner institutions in order to upgrade their timescales without the associated development costs. We have shown that they can be used to steer the frequency of a remote maser using an optical fibre link.
SST3: Nuclear Magnetic Resonance Gyroscope (NMRG) Developing a Primary Rotation Sensor Michael Larsen, Marta Luengo-Kovac, Michael Bulatowicz, Dennis Bevan, Philip Clark, Julia Flicker, Robert Griffith, James Pavell, Ashley Rothballer, Daryl Sakaida, Elliot Burke, Juan Campero, Brian Ehrsam, Steven Estrella, Gordon Morrison The Nuclear Magnetic Resonance Gyro (NMRG), under development by Northrop Grumman, has achieved near navigation grade performance in a compact package. Recent improvements include turn-key startup and ferrite magnetic shielding. NMRG is the only known primary rotation sensor.
SST4: Chip-scale optical clock with 4x10-12/&[root]&[tau] stability Zachary Newman, Vincent Maurice, Tara Drake, Jordan Stone, Travis Briles, Daryl Spencer, Cort Johnson, David M. Johnson, Leo Holberg, Scott Diddams, John Kitching, Scott Papp, Matt Hummon We report on the development of a compact, low-power optical clock based on the rubidium two-photon transition at 778 nm in a microfabricated vapor cell with a fractional stability of 3x10-13. The clock stability is transferred to the microwave domain with a Kerr-microresonator frequency comb.
SST5: 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.


TO1.1: Applications and Analysis of Resonant Devices

Moderators: Songbin Gong and Matteo Rinaldi

Paper Title Authors Executive Summary
IoT Networks: Frequency Control Considerations Roy Olsson III, Benjamin Epstein Methods are presented that describe multi-way augmentation in the operation of IoT transceivers, where the transceivers conform to emerging IoT networking standards. Implications on the frequency control of these devices is also discussed.
Enhancing Piezo-MEMS Transformer Performance Sarah Bedair, Ryan Rudy, Jeffrey Pulskamp, Iain Kierzewski, Brian Power, Joel Martin, Raphael Luo, Ryan Cable, Victor Tseng, Robert Benoit This paper documents an architecture approach using extensional mode harmonics to improve the figures of merit of thin-film piezoelectric MEMS transformers. Experiments show an improvement of over 4x in transformer figure of merit.
On the Origin of High Coupling Two-Dimensional Modes of Vibration in Aluminum Nitride Plates Cristian Cassella, Matteo Rinaldi This work discusses, for the first time through the Lamb-Wave theory, the origin of the recently reported high electromechanical coupling coefficient values (kt2) in two-dimensional modes of vibration excited in Aluminum Nitride (AlN) plates.
Investigation of Phonon-Carrier Interactions in Silicon-Based MEMS Resonators Hakhamanesh Mansoorzare, Hedy Fatemi, Reza Abdolvand In this work, a novel technique is developed for isolating the energy loss associated with the interaction of charge carriers and acoustic phonons in thin piezoelectric-on-silicon (TPoS) MEMS resonators so that this component of loss could be investigated and validated.
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.


TO1.2: Cold-Atom Microwave Clocks

Moderator: Gaetano Mileti

Paper Title Authors Executive Summary
TO121: Portable cold atom frequency standard Brian Patton  
TO122: 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+.
TO123: The first evaluation of the new fountain clock NIM6 Fang Fang, Tianchu Li, Weiliang Chen A new fountain clock has been built. It operates with a MOT loading OM. The instability of 1.6E-13 is achieved at 1 second. Both uncertainties due to second order Zeeman effect and black body radiation effect are reduced to less than 1E-16. Some other frequency shifts are under evaluating.
TO124: Compact Atomic Clock with Diffuse Laser-Cooled Atoms Liang Liu, Hua-Dong Cheng, Yan-Ling Meng, Lin Li, Jin-Yin Wan, Ming-Yuan Yu, Ya-Ning Wang, Xin Wang, Xiu-Mei Wang, Ling Xiao In a compact and robust cold atom clock, rubidium atoms are cooled by diffuse light and interrogated by microwave in a same cylindrical microwave cavity. Several factors affacting the performace of the clock are studied, and 1.8E-15/20,000s has been reached.
TO125: A Cold Atomic Beam Ramsey CPT Clock John Elgin, Thomas Heavner, John Kitching, Elizabeth Donley, Evan Salim, Jayson Denney We have developed a cold atomic beam coherent population trapping clock based on traditional two-zone Ramsey interrogation performed on the D2 line of an atomic beam of 87Rb generated from a 2D+-MOT. The current fractional frequency instability is 2.5 x 10-11τ -1/2.


TO1.3: Satellite-based Time Transfer

Moderators: Wolfgang Shaefer and Shinn-Yan Lin

TO1.3: Satellite-Based Time Transfer

Paper Title Authors Executive Summary
TO131: Bounded Asynchrony in Distributed Systems Peter Hochschild This talk addresses the principles and applications of bounded asynchrony in large-scale distributed systems.
TO132: Comparison and analysis of one-way time transfer based on GPS and CAPS constellations Jingya Chen, Longxia Xu, Xiaohui Li, Lingda Meng To compare and analysis the difference between China Area Position System (CAPS) and GPS in this article. We made a introduction of the main difference between CAPS and GPS, then we focused on a direct comparison between CAPS and GPS on one-way time transfer in theoretical and experimental way.
TO133: Improved absolute calibration of multi-GNSS reception chains at CNES Jérôme Delporte, David Valat, François-Xavier Marmet The purpose of this paper is to present our recent improvements in the absolute calibration of GNSS reception chains, with the objective to reach a sub-ns accuracy for the complete chain.
TO134: Absolute Calibration of the BDS-3 Receiver Based on Global Signal System Huang luxi, zhu feng, li xiaohui The results show BDS-3 receiver channel delays are better than ±0.1ns, the inter-frequency deviation less than 2ns without 1PPS input. While with 1PPS input, the receiver delay increases periodically with the increasing of TtP. The combined uncertainty of B1, B2 and B3 is 1.24, 1.24 and 0.58.
TO135: Strain Transfer and Creep in All-Quartz Packaged SAW Strain Sensors Victor Kalinin, Arthur Leigh, Aidrian Nowell, Clarence Pilgrim An all-quartz package (AQP) for a resonant SAW strain sensor is discussed and strain transfer in it is studied. Creep of strain in the SAW substrate is simulated using a viscoelastic model for the adhesives. An observed anomalous creep of the resonant frequencies is explained theoretically. 


TO2.1: Optical Clocks

Moderators: Franklyn Quinlan and Andre Luiten

TO2.1: Optical Clocks

Paper Title Authors Executive Summary
TO211: Toward a redefinition of the SI second with optical clocks: an overview of recent progress Sebastien Bize  
TO212: Systematic uncertainty of an 27Al+ optical atomic clock David Leibrandt, Samuel Brewer, Jwo-Sy Chen, David Hume, Aaron Hankin, Ethan Clements, Chin-Wen Chou, David Wineland We report the results of a systematic uncertainty evaluation of the third-generation NIST 27Al+ quantum-logic clock, and preliminary results from recent optical frequency ratio measurements between this clock and the NIST/JILA 171Yb and 87Sr optical lattice clocks.
TO213: 40Ca+ Ion Optical Clock with Systematic Uncertainty at 2.2&[mult]10-17 Kelin Gao, Hua Guan, Yao Huang Here we report the improvements made to reduce the systematic uncertainty at 2.2×10-17, limited by the BBR field evaluation. The differential static scalar polarizability ∆α0 of the 40Ca+ ion clock transition is measured by precisely measuring the 'magic' rf drive frequency. 
TO214: 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.
TO215: Sr lattice clocks at NPL Ian Hill, Richard Hobson, William Bowden, Marco Schioppo, Alissa Silva, Patrick Gill, Helen Margolis, Matthew Jones, Paul Huillery We have established an operational Sr optical lattice clock and evaluated its performance. A novel method for measurement of the DC Stark shift has been developed.


TO2.2: Novel Physical Sensors & Applications

Moderators: Guillermo Villanueva and Fabien Josse

Paper Title Authors Executive Summary
TO221: Novel Uses of Stabilized Optical Frequency Combs: from Regional Methane Leak Source Identification to Diagnostics for Extreme Combustion Greg Rieker, Sean Coburn, Caroline Alden, Ryan Cole, Anthony Draper, Paul Schroeder, Robert Wright, Ian Coddington, Kevin Cossel, Esther Baumann, Kuldeep Prasad, Nathan Newbury Advances in frequency comb technology are enabling new applications of laser absorption spectroscopy to practical environments. We describe two such applications – locating and sizing methane leaks across large regions, and diagnostic development for high pressure combustion systems.
TO222: Quantum sensors for magnetic field communication Vladislav Gerginov, Fabio da Silva, David Howe An optically-pumped magnetometer is chosen as a sensor for detection of low-frequency digital magnetic signals due to its sensitivity, bandwidth and size. A proof-of-principle detection of binary phase shift keying (BPSK) modulated signals is realized.


TO223: Probing Response to γ-Ray Irradiation on Semiconducting Two-Dimensional (2D) Resonators Philip Feng, Jaesung Lee We report on experimental demonstration and analytical modeling of response to γ-ray on molybdenum disulfide (MoS2) nanomechanical resonator. The results show that MoS2 resonators are robust yet sensitive to γ-ray, demonstrating a potential for detection of radiation.
TO224: 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.
TO225: Detection and Quantification of Multi-Analyte Mixtures Using a Single Sensor and Multi-Stage Data-Weighted RLSE Fabien Josse, Karthick Sothivelr, Florian Bender, Edwin E. Yaz, Antonio J. Ricco As an alternative to using sensor arrays, we report the detection and quantification of multi-analyte mixtures using time-dependent frequency shift transients from a single sensor and a signal processing technique based on multi-stage data-weighted recursive least-squares estimation.


TO2.3 - Cryogenic and Optical Oscillators

Moderator: Enrico Rubiola

Paper Title Authors Executive Summary
TO231: Brillouin photonic integrated devices for ultrahigh-resolution and broadband microwave signal processing Ben Eggleton, Amol Choudhary  
TO232: 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.
TO234: Low phase noise tunable OEO locked to a high sensitivity phase noise analyzer Naoya Kuse, Martin Fermann A tunable OEO based on a YIG filter is locked to a high sensitivity phase noise analyzer, resulting in phase noise of -89 dBc/Hz, -115 dBc/Hz -135 dBc/Hz, and -143 dBc/Hz at 100 Hz, 1 kHz, 10 kHz, and 100 kHz for 10 GHz carrier is obtained without any higher oscillation modes up to 1 MHz.
TO234: Pound Stabilized Cryogenic Bulk Acoustic Wave Resonator-Oscillator Michael Tobar, Eugene Ivanov, Maxim Goryachev, Serge Galliou We have realized a Pound stabilized cryogenic oscillator from a high-Q quartz BAW resonator at 116 MHz. Despite the extremely high Q-factors, the power-frequency sensitivity is increased by a factor of 1000 at cryogenic temperatures and limits the purity of the oscillator signal.
TO235: Direct Stability Measurement of Cryogenic Sapphire Oscillators with Tracking DDSs and Two-Sample Covariance Enrico Rubiola, Claudio Calosso, Christophe Fluhr, Benoit Dubois, Francois Vernotte, Vincent Giordano We demonstrate the first stability measurement of 10 GHz CSOs at the 100 MHz out by comparing 3 units. Using a Tracking DDS and two-sample covariances, it is no longer necessary to beat the oscillators down to the HF region. The stability is of 2×10–15 at 1 s, and 3×10–16 flicker.