Search results for "Sensor"
showing 10 items of 4594 documents
Robust optical readout and characterization of nuclear spin transitions in nitrogen-vacancy ensembles in diamond
2019
Nuclear spin ensembles in diamond are promising candidates for quantum sensing applications, including rotation sensing. Here we perform a characterization of the optically detected nuclear-spin transitions associated with the 14N nuclear spin within diamond nitrogen vacancy (NV) centers. We observe nuclear-spin-dependent fluorescence with the contrast of optically detected 14N nuclear Rabi oscillations comparable to that of the NV electron spin. Using Ramsey spectroscopy, we investigate the temperature and magnetic-field dependence of the nuclear spin transitions in the 77.5-420 K and 350-675 G range, respectively. The nuclear quadrupole coupling constant Q was found to vary with temperatu…
Relativistic quantum thermometry through a moving sensor
2023
Using a two-level moving probe, we address the temperature estimation of a static thermal bath modeled by a massless scalar field prepared in a thermal state. Different couplings of the probe to the field are discussed under various scenarios. We find that the thermometry is completely unaffected by the Lamb shift of the energy levels. We take into account the roles of probe velocity, its initial preparation, and environmental control parameters for achieving optimal temperature estimation. We show that a practical technique can be utilized to implement such a quantum thermometry. Finally, exploiting the thermal sensor moving at high velocity to probe temperature within a multiparameter-est…
Practical system for the generation of pulsed quantum frequency combs
2017
The on-chip generation of large and complex optical quantum states will enable low-cost and accessible advances for quantum technologies, such as secure communications and quantum computation. Integrated frequency combs are on-chip light sources with a broad spectrum of evenly-spaced frequency modes, commonly generated by four-wave mixing in optically-excited nonlinear micro-cavities, whose recent use for quantum state generation has provided a solution for scalable and multi-mode quantum light sources. Pulsed quantum frequency combs are of particular interest, since they allow the generation of single-frequency-mode photons, required for scaling state complexity towards, e.g., multi-photon…
Generation of multimode squeezing and entanglement in the space and frequency domains : A general “supermode” approach
2009
Optical parametric oscillators (OPO) have been extensively used in the continuous variable quantum optics community as a resource to produce non-classical states of light, including squeezed states or entangled beams. They have been widely studied, theoretically and experimentally, in the single mode case, and have found many applications to quantum information protocols and high sensitivity optical measurements. However, as the complexity of quantum information protocols increases, the need for multiplexed quantum channels has emerged, which require the use of multimode non-classical states of light.
Quantum Control in Atomic Systems
1999
We review a series of recent experiments demonstrating quantum control of atomic processes and products induced by the interaction of the atom with coherent bichromatic electromagnetic fields. Since the effects under consideration are electromagnetically induced, control is established through the field parameters i.e. frequency, amplitude and phase. The controlled processes include resonant and non resonant multiphoton ionization, autoionization, radiative decay in multiple continua (ionization branching ratios) and third harmonic generation.
Quantum technologies and the elephants
2021
Extraordinary progress in quantum sensors and technologies opens new avenues for exploring the Universe and testing the assumptions forming the basis of modern physics. This QST focus issue: focus on quantum sensors for new-physics discoveries is a next-decade roadmap on developing a wide range of quantum sensors and new technologies towards discoveries of new physics. It covers the next generation of various technologies, including atomic and nuclear clocks, atomic and diamond-based magnetometers, atom and laser interferometers, control of trapped atoms, ions, and molecules, optomechanical systems, and many others. In this editorial, we outline major problems of fundamental physics we aim …
The Lasting Influences of Early Food-Related Variety Experience: A Longitudinal Study of Vegetable Acceptance from 5 Months to 6 Years in Two Populat…
2016
International audience; Children's vegetable consumption falls below current recommendations, highlighting the need to identify strategies that can successfully promote better acceptance of vegetables. Recently, experimental studies have reported promising interventions that increase acceptance of vegetables. The first, offering infants a high variety of vegetables at weaning, increased acceptance of new foods, including vegetables. The second, offering an initially disliked vegetable at 8 subsequent meals markedly increased acceptance for that vegetable. So far, these effects have been shown to persist for at least several weeks. We now present follow-up data at 15 months, 3 and 6 years ob…
The Minimal Phenomenal Experience questionnaire (MPE-92M): Towards a phenomenological profile of “pure awareness” experiences in meditators
2021
Objective To develop a fine-grained phenomenological analysis of “pure awareness” experiences in meditators. Methods An online survey in five language versions (German, English, French, Spanish, Italian) collected data from January to March 2020. A total of 92 questionnaire items on a visual analogue scale were submitted to exploratory and confirmatory factor analysis. Results Out of 3627 submitted responses, 1403 were usable. Participants had a median age of 52 years (range: 17–88) and were evenly split between men and women (48.5% vs 50.0%). The majority of meditators practiced regularly (77.3%), were free of diagnosed mental disorders (92.4%) and did not regularly use any psychoactive s…
Quantum control and long-range quantum correlations in dynamical Casimir arrays
2015
The recent observation of the dynamical Casimir effect in a modulated superconducting waveguide, coronating thirty years of world-wide research, empowered the quantum technology community with a powerful tool to create entangled photons on-chip. In this work we show how, going beyond the single waveguide paradigm using a scalable array, it is possible to create multipartite nonclassical states, with the possibility to control the long-range quantum correlations of the emitted photons. In particular, our finite-temperature theory shows how maximally entangled $NOON$ states can be engineered in a realistic setup. The results here presented open the way to new kinds of quantum fluids of light,…
Interactions texture-flaveur : mécanismes physico-chimiques ou mécanismes cognitifs ? Application à un gel laitier onctueux
2006
Texture, taste and aroma are key components of the perceived quality of foodstuffs. Many studies showed that modifying one of thèse dimensions could modify the perception of another one. However it is not always clear whether thèse interactions could be attributed to physico-chemical or cognitive mechanisms. The présent work aimed at studying sensory interactions between texture, taste and aroma, in relation with the perception of creaminess, an indicator of food quality. A first step consisted in defining the creaminess concept using sensory and verbal approaches. This study highlighted three groups of consumers: creaminess was associated to texture for the first group, to texture and tast…