Results 21 to 30 of about 2,995,639 (168)
Publisher Correction: Chip-scale atomic diffractive optical elements
Nature Communications, 2019 An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Liron Stern +4 more
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A chip-scale atomic beam clock
Nature Communications, 2023 Atomic beams are a longstanding technology for atom-based sensors and clocks with widespread use in commercial frequency standards. Here, we report the demonstration of a chip-scale microwave atomic beam clock using coherent population trapping (CPT ...
Gabriela D. Martinez +5 more
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Time-frequency complexity and information [PDF]
Proceedings of ICASSP '94. IEEE International Conference on Acoustics, Speech and Signal Processing, 2002 Many functions have been proposed for estimating signal information content and complexity on the time-frequency plane, including moment-based measures such as the time-bandwidth product and the Shannon and Renyi(see 4th Berkeley Symp. Math., Stat., Prob., vol.1) entropies.
Patrick Flandrin +2 more
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Chip-scale atomic diffractive optical elements
Nature Communications, 2019 Quantum coherence and the nonlinear properties of atoms are highly useful in optical devices. Here the authors show quantum-optic hybrid platforms in fully integrated chip-scale atomic diffractive optical elements by embedding hot atomic Rb vapor in ...
Liron Stern +4 more
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On positivity of time-frequency distributions [PDF]
IEEE Transactions on Acoustics, Speech, and Signal Processing, 1985 Consideration is given to the problem of how to regard the fundamental impossibility with time-frequency energy distributions of Cohen's class always to be nonnegative and, at the same time, to have correct marginal distributions. It is shown that the Wigner distribution is the only member of a large class of bilinear time-frequency distributions that ...
Janssen, A.J.E.M., Claasen, T.A.C.M.
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Chip-Scale Ultra-Low Field Atomic Magnetometer Based on Coherent Population Trapping
Sensors, 2021 We report a chip-scale atomic magnetometer based on coherent population trapping, which can operate near zero magnetic field. By exploiting the asymmetric population among magnetic sublevels in the hyperfine ground state of cesium, we observe that the ...
Hyun-Gue Hong +7 more
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A proof-of-concept model of compact and high-performance 87Sr optical lattice clock for space
AIP Advances, 2021 A compact and robust design of an optical lattice clock with high stability and accuracy is needed for the implementation of optical clocks operating on the space station.
Feng Guo +13 more
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Time-frequency analysis of tremors [PDF]
Brain, 1998 Time-frequency analysis methods were applied to surface EMG records of patients with tremor. Variation in tremor frequency over time and between muscles was measured in subjects with Parkinson's disease (n = 20), essential tremor (n = 8) and psychogenic tremor (n = 7).
P E, O'Suilleabhain, J Y, Matsumoto
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Precision measurement of transverse velocity distribution of a strontium atomic beam
AIP Advances, 2014 We measure the transverse velocity distribution in a thermal Sr atomic beam precisely by velocity-selective saturated fluorescence spectroscopy. The use of an ultrastable laser system and the narrow intercombination transition line of Sr atoms mean that ...
F. Gao +7 more
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Sparse time-frequency representations [PDF]
Proceedings of the National Academy of Sciences, 2006 Auditory neurons preserve exquisite temporal information about sound features, but we do not know how the brain uses this information to process the rapidly changing sounds of the natural world. Simple arguments for effective use of temporal information led us to consider the reassignment class of time-frequency representations as ...
Gardner, Timothy J. +1 more
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