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
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Manchao Zhang ◽  
Yi Xie ◽  
Jie Zhang ◽  
Weichen Wang ◽  
Chunwang Wu ◽  
...  

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

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Sören Dörscher ◽  
Ali Al-Masoudi ◽  
Marcin Bober ◽  
Roman Schwarz ◽  
Richard Hobson ◽  
...  

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.


Author(s):  
Miguel Iglesias Olmedo ◽  
Xiaodan Pang ◽  
Molly Piels ◽  
Richard Schatz ◽  
Gunnar Jacobsen ◽  
...  

2016 ◽  
Vol 2 (10) ◽  
pp. e1601231 ◽  
Author(s):  
Matthew A. Norcia ◽  
Matthew N. Winchester ◽  
Julia R. K. Cline ◽  
James K. Thompson

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.


2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Aditya Kakkar ◽  
Jaime Rodrigo Navarro ◽  
Richard Schatz ◽  
Xiaodan Pang ◽  
Oskars Ozolins ◽  
...  

Sensors ◽  
2021 ◽  
Vol 21 (17) ◽  
pp. 5788
Author(s):  
Yanqi Zhang ◽  
Adam S. Hines ◽  
Guillermo Valdes ◽  
Felipe Guzman

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.


2021 ◽  
Author(s):  
Oliver Lux ◽  
Christian Lemmerz ◽  
Fabian Weiler ◽  
Thomas Kanitz ◽  
Denny Wernham ◽  
...  

Abstract. The acquisition of atmospheric wind profiles on a global scale was realized by the launch of the Aeolus satellite, carrying the unique Atmospheric LAser Doppler INstrument (ALADIN), the first Doppler wind lidar in space. One major component of ALADIN is its high-power, ultraviolet (UV) laser transmitter which is based on an injection-seeded, frequency-tripled Nd:YAG laser and fulfills a set of demanding requirements in terms of pulse energy, pulse length, repetition rate as well as spatial and spectral beam properties. In particular, the frequency stability of the laser emission is an essential parameter which determines the performance of the lidar instrument, as the Doppler frequency shifts to be detected are on the order of 108 smaller than the frequency of the emitted UV light. This article reports the assessment of the ALADIN laser frequency stability and its influence on the quality of the Aeolus wind data. Excellent frequency stability with pulse-to-pulse variations of about 10 MHz (root mean square) is evident for over more than two years of operations in space despite the permanent occurrence of short periods with significantly enhanced frequency noise (> 30 MHz). The latter were found to coincide with specific rotation speeds of the satellite's reaction wheels, suggesting that the root cause are micro-vibrations that deteriorate the laser stability on time scales of a few tens of seconds. Analysis of the Aeolus wind error with respect to ECMWF model winds shows that the temporally degraded frequency stability of the ALADIN laser transmitter has only minor influence on the wind data quality on a global scale, which is primarily due to the small percentage of wind measurements for which the frequency fluctuations are considerably enhanced. Hence, although the Mie wind bias is increased by 0.3 m·s−1 at times when the frequency stability is worse than 20 MHz, the small contribution of 4 % from all wind results renders this effect insignificant (


Sign in / Sign up

Export Citation Format

Share Document