Laser frequency noise immunity in multiplexed displacement sensing

2011 ◽  
Vol 36 (5) ◽  
pp. 672 ◽  
Author(s):  
Danielle M. R. Wuchenich ◽  
Timothy T.-Y. Lam ◽  
Jong H. Chow ◽  
David E. McClelland ◽  
Daniel A. Shaddock
Keyword(s):  
Noise Immunity ◽  
Laser Frequency ◽  
Frequency Noise

scholarly journals Estimation of the Laser Frequency Noise Spectrum by Continuous Dynamical Decoupling

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Manchao Zhang ◽  
Yi Xie ◽  
Jie Zhang ◽  
Weichen Wang ◽  
Chunwang Wu ◽  
...  
Keyword(s):  
Noise Spectrum ◽  
Laser Frequency ◽  
Frequency Noise ◽  
Dynamical Decoupling

scholarly journals Impact of laser frequency noise on high-extinction optical modulation

2020 ◽  
Vol 28 (26) ◽  
pp. 39606
Author(s):  
Gavin N. West ◽  
William Loh ◽  
Dave Kharas ◽  
Rajeev J. Ram
Keyword(s):  
Laser Frequency ◽  
Optical Modulation ◽  
Frequency Noise

scholarly journals Dynamical decoupling of laser phase noise in compound atomic clocks

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Sören Dörscher ◽  
Ali Al-Masoudi ◽  
Marcin Bober ◽  
Roman Schwarz ◽  
Richard Hobson ◽  
...  
Keyword(s):  
Phase Noise ◽  
Phase Measurement ◽  
Local Oscillator ◽  
Frequency Instability ◽  
Laser Frequency ◽  
High Signal ◽  
Frequency Noise ◽  
Atomic Clocks ◽  
Dynamical Decoupling ◽  
Measurement Protocol

Abstract The frequency stability of many optical atomic clocks is limited by the coherence of their local oscillator. Here, we present a measurement protocol that overcomes the laser coherence limit. It relies on engineered dynamical decoupling of laser phase noise and near-synchronous interrogation of two clocks. One clock coarsely tracks the laser phase using dynamical decoupling; the other refines this estimate using a high-resolution phase measurement. While the former needs to have a high signal-to-noise ratio, the latter clock may operate with any number of particles. The protocol effectively enables minute-long Ramsey interrogation for coherence times of few seconds as provided by the current best ultrastable laser systems. We demonstrate implementation of the protocol in a realistic proof-of-principle experiment, where we interrogate for 0.5 s at a laser coherence time of 77 ms. Here, a single lattice clock is used to emulate synchronous interrogation of two separate clocks in the presence of artificial laser frequency noise. We discuss the frequency instability of a single-ion clock that would result from using the protocol for stabilisation, under these conditions and for minute-long interrogation, and find expected instabilities of σy(τ) = 8 × 10−16(τ/s)−1/2 and σy(τ) = 5 × 10−17(τ/s)−1/2, respectively.

scholarly journals Noise Immunity Analysis and Improvement of dq Frame Based Open-Loop Phase Detection Scheme

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1145
Author(s):  
Xiaobo Li ◽  
Mingxian Li ◽  
Hua Chai ◽  
Binbing Wu
Keyword(s):  
High Frequency ◽  
Noise Immunity ◽  
Open Loop ◽  
Fine Tuning ◽  
Frequency Noise ◽  
Phase Detection ◽  
Detection Error ◽  
Pass Filter ◽  
High Frequency Noise ◽  
Grid Voltage

To improve the noise immunity of a dq frame based open-loop phase detection (OPD) under high-frequency noise grid conditions, this paper develops a detailed model to quantitatively evaluate the phase detection error and noise immunity. It is found that the OPD behaves differently in terms of noise immunity when the dq frame is in different angle positions with the grid voltage. When the grid voltage coincides with the d axis, the high-frequency noise has the smallest impact on the phase detection accuracy, and the OPD thus has the strongest noise immunity. Inspired by this conclusion, an improved OPD algorithm is proposed in this paper, which can effectively reduce the phase detection error by fine-tuning the rotation angle of the dq frame to ensure that the angle between the voltage vector and d axis is always close to 0. The improved OPD algorithm has a fast and precise character to detect the phase information with less error and is flexible for application. Under heavy noise grid conditions, it can also effectively shorten the dynamic response time in the phase-detecting process using a low-pass filter (LPF) with a higher cut-off frequency. The correctness of the noise immunity analysis and the effectiveness of the improved OPD algorithm are verified by the simulations and experimental results in MATLAB and RT-LAB.

Carrier Recovery Techniques for Semiconductor Laser Frequency Noise for 28 Gbd DP-16QAM

2015 ◽  
Author(s):  
Miguel Iglesias Olmedo ◽  
Xiaodan Pang ◽  
Molly Piels ◽  
Richard Schatz ◽  
Gunnar Jacobsen ◽  
...  
Keyword(s):  
Semiconductor Laser ◽  
Laser Frequency ◽  
Frequency Noise ◽  
Carrier Recovery ◽  
Recovery Techniques

scholarly journals Superradiance on the millihertz linewidth strontium clock transition

2016 ◽  
Vol 2 (10) ◽  
pp. e1601231 ◽  
Author(s):  
Matthew A. Norcia ◽  
Matthew N. Winchester ◽  
Julia R. K. Cline ◽  
James K. Thompson
Keyword(s):  
Cavity Mode ◽  
Optical Cavity ◽  
Atomic Clock ◽  
Laser Frequency ◽  
Gain Medium ◽  
Optical Clock ◽  
Frequency Noise ◽  
Clock Transition ◽  
Reference Cavity ◽  
High Finesse

Laser frequency noise contributes a significant limitation to today’s best atomic clocks. A proposed solution to this problem is to create a superradiant laser using an optical clock transition as its gain medium. This laser would act as an active atomic clock and would be highly immune to the fluctuations in reference cavity length that limit today’s best lasers. We demonstrate and characterize superradiant emission from the millihertz linewidth clock transition in an ensemble of laser-cooled 87Sr atoms trapped within a high-finesse optical cavity. We measure a collective enhancement of the emission rate into the cavity mode by a factor of more than 10,000 compared to independently radiating atoms. We also demonstrate a method for seeding superradiant emission and observe interference between two independent transitions lasing simultaneously. We use this interference to characterize the relative spectral properties of the two lasing subensembles.

scholarly journals Laser Frequency Noise in Coherent Optical Systems: Spectral Regimes and Impairments

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Aditya Kakkar ◽  
Jaime Rodrigo Navarro ◽  
Richard Schatz ◽  
Xiaodan Pang ◽  
Oskars Ozolins ◽  
...  
Keyword(s):  
Laser Frequency ◽  
Optical Systems ◽  
Frequency Noise

scholarly journals Investigation and Mitigation of Noise Contributions in a Compact Heterodyne Interferometer

Sensors ◽  
2021 ◽  
Vol 21 (17) ◽  
pp. 5788
Author(s):  
Yanqi Zhang ◽  
Adam S. Hines ◽  
Guillermo Valdes ◽  
Felipe Guzman
Keyword(s):  
Noise Source ◽  
Laser Frequency ◽  
Noise Estimation ◽  
Frequency Noise ◽  
Correction Algorithm ◽  
Dynamic Measurements ◽  
Heterodyne Interferometer ◽  
Order Of Magnitude ◽  
Noise Correction ◽  
Laser Interferometers

We present a noise estimation and subtraction algorithm capable of increasing the sensitivity of heterodyne laser interferometers by one order of magnitude. The heterodyne interferometer is specially designed for dynamic measurements of a test mass in the application of sub-Hz inertial sensing. A noise floor of 3.31×10−11m/Hz at 100 mHz is achieved after applying our noise subtraction algorithm to a benchtop prototype interferometer that showed a noise level of 2.76×10−10m/Hz at 100 mHz when tested in vacuum at levels of 3×10−5 Torr. Based on the previous results, we investigated noise estimation and subtraction techniques of non-linear optical pathlength noise, laser frequency noise, and temperature fluctuations in heterodyne laser interferometers. For each noise source, we identified its contribution and removed it from the measurement by linear fitting or a spectral analysis algorithm. The noise correction algorithm we present in this article can be generally applied to heterodyne laser interferometers.

Sign in / Sign up

Export Citation Format

Share Document