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Optomechanical backaction processes in a bulk rare-earth doped crystal [article]

Anne Louchet-Chauvet and Pierre Verlot and Jean-Philippe Poizat and Thierry Chanelière
2021 arXiv   pre-print
Aside from quantum optomechanics, this so-called piezospectroscopic effect offers interesting applications as a sensi- * tive strain probe in bulk materials [14] [15] [16  ... 
arXiv:2109.06577v1 fatcat:l4bynekbazd2fexxqvgjmvf26i

Structured ultrasound-modulated optical tomography

Maïmouna Bocoum, Jean-Luc Gennisson, Jean-Baptiste Laudereau, Anne Louchet-Chauvet, Jean-Michel Tualle, François Ramaz
2019 Applied Optics  
Ultrasound-modulated optical tomography (UOT) is an imaging technique that couples light and ultrasound in order to perform in-depth imaging of highly scattering media. In previous work, we introduced plane wave UOT, an imaging method analogous to x-ray tomography based on the filtered backprojection for image reconstruction. Angle-limited measurements, however, led to drastic loss of lateral spatial resolution. Here, we present a new structured ultrasonic plane wave UOT method that allows
more » ... al recovery of the resolution. For image reconstruction, we present a generalization of the Fourier slice theorem along with a generalized filtered backprojection formalism. The method is successfully tested on simulated and experimental data.
doi:10.1364/ao.58.001933 fatcat:gtuae7eobjetdd5lorkbzguxxm

Limits to the sensitivity of a rare-earth-enabled cryogenic vibration sensor [article]

Anne Louchet-Chauvet, Thierry Chanelière
2022 arXiv   pre-print
Cryogenics is a pivotal aspect in the development of quantum technologies. Closed-cycle devices have recently emerged as an environmentally friendly and low-maintenance alternative to liquid helium cryostats. Yet the larger level of vibrations in dry cryocoolers forbids their use in most sensitive applications. In a recent work, we have proposed an inertial, broadband, contactless sensor based on the piezospectroscopic effect, ie the natural sensitivity of optical lines to strain exhibited by
more » ... purities in solids. This sensor builds on the exceptional spectroscopic properties of rare earth ions and operates below 4K, where spectral hole burning considerably enhances the sensitivity. In this paper, we investigate the fundamental and technical limitations of this vibration sensor by comparing a rigid sample attachment to cold stage of a pulse-tube cryocooler and a custom-designed exchange gas chamber for acoustic isolation.
arXiv:2112.03713v2 fatcat:m6ebpuxa2fb4he7w3jfkaoztom

Large efficiency at telecom wavelength for optical quantum memories

Julián Dajczgewand, Jean-Louis Le Gouët, Anne Louchet-Chauvet, Thierry Chanelière
2014 Optics Letters  
We implement the ROSE protocol in an erbium doped solid, compatible with the telecom range. The ROSE scheme is an adaptation of the standard 2-pulse photon echo to make it suitable for a quantum memory. We observe an efficiency of 40% in a forward direction by using specific orientations of the light polarizations, magnetic field and crystal axes.
doi:10.1364/ol.39.002711 pmid:24784084 fatcat:ggr4n6zaazfrjcjuoin7zkj6x4

Entanglement-assisted atomic clock beyond the projection noise limit

Anne Louchet-Chauvet, Jürgen Appel, Jelmer J Renema, Daniel Oblak, Niels Kjaergaard, Eugene S Polzik
2010 New Journal of Physics  
We use a quantum non-demolition measurement to generate a spin squeezed state and to create entanglement in a cloud of 10^5 cold cesium atoms, and for the first time operate an atomic clock improved by spin squeezing beyond the projection noise limit in a proof-of-principle experiment. For a clock-interrogation time of 10 \mu\s the experiments show an improvement of 1.1 dB in the signal-to-noise ratio, compared to the atomic projection noise limit.
doi:10.1088/1367-2630/12/6/065032 fatcat:55s2xgm4irc5xdtor4r3hxq4uy

Piezospectroscopic measurement of high-frequency vibrations in a pulse-tube cryostat

Anne Louchet-Chauvet, Rose Ahlefeldt, Thierry Chanelière
2019 Review of Scientific Instruments  
Vibrations in cryocoolers are a recurrent concern to the end user. They appear in different parts of the acoustic spectrum depending on the refrigerator type, Gifford McMahon or pulse-tube, and with a variable coupling strength to the physical system under interest. Here, we use the piezospectroscopic effect in rare-earth doped crystals at low temperature as a high resolution, contact-less probe for the vibrations. With this optical spectroscopic technique, we obtain and analyze the vibration
more » ... ectrum up to 700kHz of a 2kW pulse-tube cooler. We attempt an absolute calibration based on known experimental parameters to make our method partially quantitative and to provide a possible comparison with other well-established techniques.
doi:10.1063/1.5080086 fatcat:jsiaholdtjhoznppqklrgihnca

20 GHz instantaneous bandwidth RF spectrum analyzer with high time-resolution

Perrine Berger, Muriel Schwarz, Stephanie Molin, Daniel Dolfi, Loic Morvan, Anne Louchet-Chauvet, Thierry Chaneliere, Jean-Louis Le Gouet
2014 Microwave Photonics (MWP) and the 2014 9th Asia-Pacific Microwave Photonics Conference (APMP) 2014 International Topical Meeting on  
We report on the experimental demonstration of a multi-gigahertz bandwidth RF spectrum analyzer exhibiting a resolution below 20 MHz, based on spectral hole burning in a rare-earth ion-doped crystal. To be compatible with demanding real-time spectrum monitoring applications, our demonstrator is designed to reach a high time resolution. For this purpose, we implemented the so-called "rainbow" architecture in which the spectral components of the incoming signal are angularly separated by the
more » ... al, and are then acquired with a pixelated photodetector. The Tm 3+ :YAG crystal is programmed with a semiconductor DFB laser which frequency scan is servocontrolled and synchronized with the angular scan of a resonant galvanometric mirror, while a high-speed camera is used to acquire the spectra. In the perspective of future implementation within a system, the crystal is cooled below 4 K with a closedcycle cryostat. With this setup, we have been able to monitor and record the spectrum of complex microwave signals over an instantaneous bandwidth above 20 GHz, with a time resolution below 100 µs, 400 resolvable frequency components and a probability of intercept of 100 %. Keywords-Analog optical signal processing, spectrum analysis, broadband microwave spectrum monitoring, spectral hole burning.
doi:10.1109/mwp.2014.6994566 fatcat:4x22g3ghpvct3mi7naxpnln67e

Ultrasound-modulated optical tomography in scattering media: flux filtering based on persistent spectral hole burning in the optical diagnosis window

Caroline Venet, Maïmouna Bocoum, Jean-Baptiste Laudereau, Thierry Chaneliere, François Ramaz, Anne Louchet-Chauvet
2018 Optics Letters  
Ultrasound modulated optical tomography (UOT) is a powerful imaging technique to discriminate healthy from unhealthy biological tissues based on their optical signature. Among the numerous detection techniques developed for acousto-optic imaging, only those based on spectral filtering are intrinsically immune to speckle decorrelation. This paper reports on UOT imaging based on spectral hole burning in Tm:YAG crystal under a moderate magnetic field (200G) with a well-defined orientation. The
more » ... and long-lasting holes translate into a more efficient UOT imaging with a higher contrast and faster imaging frame rate. We demonstrate the potential of this method by imaging calibrated phantom scattering gels.
doi:10.1364/ol.43.003993 pmid:30106935 fatcat:kqlxuafnqvbpxlhng4pyx2pboy

Comparison of 3 Absolute Gravimeters Based on Different Methods for the e-MASS Project

Anne Louchet-Chauvet, Sébastien Merlet, Quentin Bodart, Arnaud Landragin, Franck Pereira Dos Santos, Henri Baumann, Giancarlo D'Agostino, Claudio Origlia
2011 IEEE Transactions on Instrumentation and Measurement  
Louchet-Chauvet, S. Merlet II. PRESENTATION OF THE THREE GRAVIMETERS The three gravimeters involved in the comparison are national references for their respective country.  ... 
doi:10.1109/tim.2010.2099951 fatcat:julssdtybfcybcqvvlhrz2bmqa

First evaluation of an absolute quantum gravimeter (AQG#B01) for future field experiments

Anne-Karin Cooke, Cédric Champollion, Nicolas Le Moigne
2021 Geoscientific Instrumentation, Methods and Data Systems  
., 2001; Louchet-Chauvet et al., 2011) .  ...  As in Louchet-Chauvet et al. (2011) , the tests were carried out under the assumption that parameters do not change between the measurements.  ... 
doi:10.5194/gi-10-65-2021 fatcat:6rthb77pwfbaxgbznnt7klilzm

Accurate trajectory alignment in cold-atom interferometers with separated laser beams [article]

M. Altorio, L. A. Sidorenkov, R. Gautier, D. Savoie, A. Landragin and R. Geiger
2019 arXiv   pre-print
[ 1 ] 1 Anne Louchet-Chauvet, Tristan Farah, Quentin Bodart, André Clairon, Arnaud Landragin, Sébastien Merlet, and Franck Pereira Dos Santos, "The influence of trans-verse motion within an atomic gravimeter  ... 
arXiv:1912.04793v1 fatcat:t64hmavjebfdjijfovpo3gykuy