共查询到20条相似文献,搜索用时 11 毫秒
1.
We present a method of analysis involving ellipse-specific fitting of sinusoidally coupled data from two gravimeters in a gradiometer configuration. This method permits rapid extraction of induced gradient phase shifts in the presence of common-mode vibrational phase noise. Gravity gradients can be accurately measured in the presence of large vibrational accelerations. 相似文献
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We present a new general design approach of a broad-band detector of gravitational radiation that relies on two atom interferometers
separated by a distance L. In this scheme, only one arm and one laser will be used for operating the two atom interferometers. We consider atoms in
the atom interferometers not only as perfect inertial reference sensors, but also as highly stable clocks. Atomic coherence
is intrinsically stable and can be many orders of magnitude more stable than a laser. The unique one-laser configuration allows
us to then apply time-delay interferometry to the responses of the two atom interferometers, thereby canceling the laser phase
fluctuations while preserving the gravitational wave signal in the resulting data set. Our approach appears very promising.
We plan to investigate further its practicality and detailed sensitivity analysis. 相似文献
3.
We report on a study of the dynamics of decoherence of a matter-wave interferometer, consisting of a pair of low-dimensional cold atom condensates at finite temperature. We identify two distinct regimes in the time dependence of the coherence factor of the interferometer: quantum and classical. Explicit analytical results are obtained in both regimes. In particular, in the two-dimensional case in the classical (long time) regime, we find that the dynamics of decoherence is universal, exhibiting a power-law decay with an exponent, proportional to the ratio of the temperature to the Kosterlitz-Thouless temperature of a single 2D condensate. In the one-dimensional case in the classical regime we find a universal nonanalytic time dependence of decoherence, which is a consequence of the nonhydrodynamic nature of damping in 1D liquids. 相似文献
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High-order inertial phase shifts are calculated for time-domain atom interferometers. We obtain closed-form analytic expressions for these shifts in accelerometer, gyroscope, optical clock and photon recoil measurement configurations. Our analysis includes Coriolis, centrifugal, gravitational, and gravity gradient-induced forces. We identify new shifts which arise at levels relevant to current and planned experiments. PACS 39.20.+Q; 32.80.Pj; 03.75.Dg; 04.80.-Y 相似文献
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Common-mode noise rejection using fringe-locking method in WEP test by simultaneous dual-species atom interferometers 下载免费PDF全文
We theoretically investigate the application of the fringe-locking method(FLM) in the dual-species quantum test of the weak equivalence principle(WEP).With the FLM,the measurement is performed invariably at the midfringe,and the extraction of the phase shift for atom interferometers is linearized.For the simultaneous interferometers,this linearization enables a good common-mode rejection of vibration noise,which is usually the main limit for high precision WEP tests of the dual-species kind.We note that this method also allows for an unbiased determination of the gravity accelerations difference,which meanwhile is ready to be implemented. 相似文献
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A. Miffre M. Jacquey M. Büchner G. Trénec J. Vigué 《Applied physics. B, Lasers and optics》2006,84(4):617-625
The high inertial sensitivity of atom interferometers has been used to build accelerometers and gyrometers, but this property makes these interferometers very sensitive to the laboratory seismic noise. This seismic noise induces a phase noise which is large enough to reduce the fringe visibility in many cases. We develop here a model calculation of this phase noise applicable to a wide class of Mach–Zehnder atom interferometers and we apply this model to our thermal lithium interferometer. We are thus able to explain the observed dependence of the fringe visibility on the diffraction order. The dynamical model developed in the present paper should be very useful to further reduce this phase noise in atom interferometers and this reduction should open the way to improved interferometers. PACS 03.75.Dg; 39.20.+q; 42.50.Vk 相似文献
10.
A. Joyet G. Di Domenico P. Thomann 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2012,66(3):61
We present a theoretical analysis of aliasing noises that might appear in cold atom
Mach-Zehnder interferometers used for the measurement of various physical quantities. We
focus more specifically on single cold atom gyroscopes. To evaluate the level of aliasing
noises, we have developed a model based on the power spectral densities of the different
identified noise sources as input parameters and which makes use of a servo-loop to
realize a precise measurement of the rotation rate. The model allows one to take into
account different modes of operation, like a continuous as well as a pulsed or even a
multi-ball operation. For monokinetic atoms, we show that the intermodulation noise can be
completely filtered out with a continuous mode of operation and an optimum modulation
scheme for any modulation frequency but also with a pulsed operation however only for
specific launching frequencies. In the case of a real continuous atomic beam having a
velocity distribution, it comes out that a high attenuation can be reached which indicates
clearly the potential stability improvement that can be expected from a continuous
operation. 相似文献
11.
J. Le Gouët P. Cheinet J. Kim D. Holleville A. Clairon A. Landragin F. Pereira Dos Santos 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(3):419-425
In atom interferometers based on two photon transitions,
the delay induced by the difference of the laser beams paths makes
the interferometer sensitive to the fluctuations of the frequency
of the lasers. We first study, in the general case, how the laser
frequency noise affects the performance of the interferometer
measurement. Our calculations are compared with the measurements
performed on our cold atom gravimeter based on stimulated Raman
transitions. We finally extend this study to the case of cold atom
gradiometers. 相似文献
12.
Phase-locked, low-noise, frequency agile titanium:sapphire lasers for simultaneous atom interferometers 总被引:1,自引:0,他引:1
We demonstrate a laser system consisting of a >1.6 W titanium:sapphire laser that is phase locked to another free-running titanium:sapphire laser at a wavelength of 852 nm with a phase noise of -138 dBc/Hz at 1 MHz from the carrier, using an intracavity electro-optic phase modulator. The residual phase variance is 2.5 x 10(-8) rad2 integrated from 1 Hz to 10 kHz. This system can phase-continuously change the offset frequency within 200 ns with frequency steps up to 4 MHz. Simultaneous atom interferometers can make full use of this ultralow phase noise in differential measurements, where influences from the vibration of optics are greatly suppressed in common mode. 相似文献
13.
L. Maleki 《General Relativity and Gravitation》2008,40(5):895-905
Precision clocks and interferometers in space can test relativistic gravity with extremely high sensitivity. Yet, only a single
such test has been performed, namely the celebrated flight of a hydrogen maser in a sub-orbital trajectory in 1976 (GP-A mission).
This paper suggests some of the obstacles to space flight of precision instruments, and describes how the emergence of new
technology might offer a pathway for removing those obstacles. A brief review of emerging technologies is made, and new mission
concepts based on them are described. Some of the technologies that can impact more tests of relativistic gravity in space
at a more distant future are also described. 相似文献
14.
Inelastic effects arising from electron-phonon coupling in molecular Aharonov-Bohm (AB) interferometers are studied using the nonequilibrium Green's function method. Results for the magnetoconductance are compared for different values of the electron-phonon coupling strength. At low-bias voltages, the coupling to the phonons does not change the lifetime and leads mainly to scattering phase shifts of the conducting electrons. As a result of these dephasing processes, the magnetoconductance of the molecular AB interferometer becomes more sensitive to the threading magnetic flux as the electron-phonon coupling is increased, opposite to the behavior of an electric gate. 相似文献
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Comparison of the sensitivities for atom interferometers in two different operation methods 下载免费PDF全文
We investigated the sensitivities of atom interferometers in the usual fringe-scanning method(FSM) versus the fringelocking method(FLM). The theoretical analysis shows that for typical noises in atom interferometers, the FSM will degrade the sensitivity while the FLM does not. The sensitivity-improvement factor of the FLM over the FSM depends on the type of noises, which is validated by numerical simulations. The detailed quantitative analysis on this fundamental issue is presented, and our analysis is readily extendable to other kinds of noises as well as other fringe shapes in addition to a cosine one. 相似文献
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等效原理是广义相对论的两个基本假设之一,也是爱因斯坦对弱等效原理的推广.目前,大量实验证明弱等效原理在一定的实验精度内是成立的.将引力与标准模型统一起来的新理论都要求弱等效原理破缺,因此更高精度的弱等效原理检验具有重要的科学意义.本文介绍了原子干涉仪的原理,回顾了利用原子干涉仪开展微观粒子弱等效原理检验实验研究的历史和现状,介绍了双组分原子干涉仪检验弱等效原理实验涉及的振动噪声抑制、拉曼光移频与相位噪声抑制、四波双衍射拉曼跃迁原子干涉、信号探测与数据处理等关键问题及研究进展,分析了高精度微观粒子弱等效原理检验研究的发展趋势,介绍了长基线原子干涉仪、空间原子干涉仪、超冷原子源以及纠缠原子源制备等方面的研究动态,展望了微观粒子弱等效原理检验研究的发展前景. 相似文献
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General Relativity and Gravitation - This paper presents a novel path integral formalism for Einstein’s theory of gravitation from the viewpoint of optimal control theory. Despite its close... 相似文献
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F. Lenz 《Zeitschrift für Physik A Hadrons and Nuclei》1972,249(5):462-464
The path length differencefΔS is estimated between two rays in an electron interferometer which are reflected on electron mirrors with a height difference ΔS. In a light optical interferometer the factorf equals 2, but in electron opticsf is smaller (1 <f < 2). The faster the perturbation of the equipotentials due to the surface profile of the mirror dies out with increasing distance from the mirror surface, the smaller is the value off. 相似文献