The Experts below are selected from a list of 11787 Experts worldwide ranked by ideXlab platform

Benjamin Bloom - One of the best experts on this subject based on the ideXlab platform.

Rodolphe Boudot - One of the best experts on this subject based on the ideXlab platform.

  • Electromagnetically induced absorption scheme for vapor-cell Atomic Clock
    Optics Express, 2019
    Co-Authors: Denis Brazhnikov, Stepan Ignatovich, Vladislav Vishnyakov, Rodolphe Boudot, Mikhail Skvortsov
    Abstract:

    A dual-frequency light field scheme, composed of counterpropagating pump and probe light waves with equal circular polarizations and different intensities, is proposed for the detection of subnatural-linewidth electromagnetically induced absorption (EIA) resonances. In this scheme, the bright-type EIA resonance is obtained at fixed static magnetic field by tuning the frequency difference between both optical fields and can be used as a frequency reference in an Atomic Clock. Using a 5-mm long buffer-gas-filled Cs vapor cell, an EIA-based Atomic Clock with a short-term fractional frequency stability of 5.8 × 10−12 τ−1/2 until 20 s integration time is reported. These performances are found to be in correct agreement with the signal-to-noise/linewidth ratio of the resonance. The proposed EIA scheme can be considered as an alternative approach to the coherent population trapping (CPT) technique for the development of compact Atomic Clocks and sensors.

  • Characterization of 894.6 nm VCSELs and application to a microcell-based Atomic Clock
    2017
    Co-Authors: Rémy Vicarini, Serge Galliou, Christophe Gorecki, Jaroslaw Rutkowski, Vincent Maurice, Eric Kroemer, Rodolphe Boudot
    Abstract:

    We report the characterization of 894.6 nm verticalcavity surface-emitting lasers (VCSELs). The laser RIN is -105 dB/Hz at 1 Hz offset frequency for a laser power of 50 μW. The laser spectral linewidth is measured to be about 31.8 MHz. Such a VCSEL is used in a Cs-Ne microcell-based Atomic Clock prototype based on coherent population trapping (CPT). A preliminary fractional frequency stability of 3.8 10-11 τ-1/2 up to 1000 s and lower than 3 10-11 at 60 000 s averaging time is reported. Further tests are in progress to improve the Clock mid-term and long-term frequency stability.

  • a high performance raman ramsey cs vapor cell Atomic Clock
    Journal of Applied Physics, 2017
    Co-Authors: Moustafa Abdel Hafiz, Peter Yun, Gregoire Coget, Stephane Guerandel, Emeric De Clercq, Rodolphe Boudot
    Abstract:

    We demonstrate a high-performance coherent-population-trapping (CPT) Cs vapor cell Atomic Clock using the push-pull optical pumping technique in the pulsed regime, allowing the detection of high-contrast and narrow Ramsey-CPT fringes. The impact of several experimental parameters onto the Clock resonance and short-term fractional frequency stability, including the laser power, the cell temperature, and the Ramsey sequence parameters, has been investigated. We observe and explain the existence of a slight dependence on laser power of the central Ramsey-CPT fringe line-width in the pulsed regime. We report also that the central fringe line-width is commonly narrower than the expected Ramsey line-width given by 1 / ( 2 T R ), with TR the free-evolution time, for short values of TR. The Clock demonstrates a short-term fractional frequency stability at the level of 2.3 × 10 − 13 τ − 1 / 2 up to 100 s averaging time, mainly limited by the laser amplitude modulation noise. Comparable performances are obtained ...

  • A high-performance CPT-based Cs vapor cell Atomic Clock using pushpull optical pumping
    2016
    Co-Authors: Moustafa Abdel Hafiz, Rodolphe Boudot
    Abstract:

    Microwave vapor cell Atomic Clocks are exciting candidates for numerous timekeeping applications because they combine compactness, a modest power consumption and excellent fractional frequency stability at the level of a few 10-13 t-1/2 [1,2,3]. In the frame of the MClocks project funded by EURAMET, we report on the development of a Cs vapor cell Atomic Clock based on coherent population trapping (CPT).

  • A low phase noise microwave frequency synthesis for a high-performance cesium vapor cell Atomic Clock
    Review of Scientific Instruments, 2014
    Co-Authors: Bruno Francois, Claudio Calosso, J. M. Danet, Rodolphe Boudot
    Abstract:

    We report the development, absolute phase noise, and residual phase noise characterization of a 9.192 GHz microwave frequency synthesis chain devoted to be used as a local oscillator in a high-performance cesium vapor cell Atomic Clock based on coherent population trapping (CPT). It is based on frequency multiplication of an ultra-low phase noise 100 MHz oven-controlled quartz crystal oscillator using a nonlinear transmission line-based chain. Absolute phase noise performances of the 9.192 GHz output signal are measured to be −42, −100, −117 dB rad2/Hz and −129 dB rad2/Hz at 1 Hz, 100 Hz, 1 kHz, and 10 kHz offset frequencies, respectively. Compared to current results obtained in a state-of-the-art CPT-based frequency standard developed at LNE-SYRTE, this represents an improvement of 8 dB and 10 dB at f = 166 Hz and f = 10 kHz, respectively. With such performances, the expected Dick effect contribution to the Atomic Clock short term frequency stability is reported at a level of 6.2 × 10−14 at 1 s integration time, that is a factor 3 higher than the Atomic Clock shot noise limit. Main limitations are pointed out.

Travis Nicholson - One of the best experts on this subject based on the ideXlab platform.

G. E. Marti - One of the best experts on this subject based on the ideXlab platform.

Ross Hutson - One of the best experts on this subject based on the ideXlab platform.