共查询到20条相似文献,搜索用时 15 毫秒
1.
T. Müller M. Gilowski M. Zaiser P. Berg Ch. Schubert T. Wendrich W. Ertmer E. M. Rasel 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,53(3):273-281
We present a compact and transportable inertial sensor for
precision sensing of rotations and accelerations. The sensor consists
of a dual atom interferometer operated with laser-cooled 87Rb.
Raman processes are employed to coherently manipulate the matter
waves. We describe and characterize the experimental apparatus. A
method for passing from a compact geometry to an extended
interferometer with three independent atom-light interaction zones is
proposed and investigated. The extended geometry will enhance the
sensitivity by more than two orders of magnitude which is necessary
to achieve sensitivities better than 10-8rad/s/. 相似文献
2.
S. Gleyzes A. El Amili R. A. Cornelussen P. Lalanne C. I. Westbrook A. Aspect J. Estève G. Moreau A. Martinez X. Lafosse L. Ferlazzo J. C. Harmand D. Mailly A. Ramdane 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,53(1):107-111
We study a Fabry-Perot cavity formed from a ridge waveguide on a AlGaAs substrate. We experimentally determined the propagation
losses in the waveguide at 780 nm, the wavelength of Rb atoms. We have also made a numerical and analytical estimate of the
losses induced by the presence of the gap which would allow the interaction of cold atoms with the cavity field. We found
that the intrinsic finesse of the gapped cavity can be on the order of F∼30, which, when one takes into account the losses
due to mirror transmission, corresponds to a cooperativity parameter for our system C∼1. 相似文献
3.
Z. Y. Wang Z. Zhang Q. Lin 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,53(2):127-131
In this paper, we proposed new constructions of atom interferometers manipulated through the toroidal trap formed by the interference
patterns of two co-propagation Laguerre-Gaussian (LG) beams. The coherent splitting and merging of the atomic ensemble, which
is essential for the atom interferometer, is realized by the interference pattern of two LG beams. Along the beam propagation
direction, a single-well trap is evolved into a double-well trap and then recombined back into a single-well trap, which can
be used to form an atom interferometer. 相似文献
4.
A. González Ureña A. Requena A. Bastida J. Zúñiga 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,49(3):297-303
A molecular beam interference model is presented based on a two-state interaction between a polar molecule and a resonant
RF field as it occurs in the so-called C-field of a typical molecular beam electric resonant spectrometer. The treatment shows the onset of interferences in the beam
transmission spectra as well as in its transverse profile. It is demonstrated how the molecular interferences are originated
by the wavefunction phase shift introduced by the resonant RF field. Furthermore it is shown that for a given beam velocity
and oscillating field frequency the fringes’ visibility depends on the strength of the RF field, i.e. the Rabi frequency,
in the transmission spectra. Likewise the presence of a RF field gradient in the perpendicular beam direction gives rise to
a peak structure in the transverse beam profile. The theoretical model was applied to simulate a variety of beam transmission
spectra under resonant conditions as well as some experimental data already published by our group showing a satisfactory
agreement between experimental and simulated data. Finally, the potentiality of this internal state molecular interferometer
to carry out studies in matter-wave interferometry is remarked. 相似文献
5.
J. Grucker J. Baudon F. Perales G. Dutier V. Bocvarski J.-C. Karam G. Vassilev M. Ducloy 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,47(3):427-431
Surface-induced exo-energetic inelastic transitions among atomic Zeeman
states in a magnetic field (“van der Waals – Zeeman” transitions) are
useable as tuneable beam splitters. A transversally coherent atom beam
impinging a pair of opposite surfaces (e.g. 2 edges of a slit or of an ensemble
of periodic slits) gives rise to two coherently diffracted wave packets.
Within the wave packet overlap, non-localised interference fringes of the
Young-slit type are predicted. From the diffraction pattern observed in the
Fraunhofer regime (Schlieren image), detailed information about the
transition amplitude on a scale of a few nanometers should be derived. 相似文献
6.
We discuss a strongly entangled two-particle state of motion that emerges naturally from the double-pulse dissociation of
a diatomic molecule. This state, which may be called dissociation-time entangled, permits the unambiguous demonstration of
nonclassical correlations by violating a Bell inequality based on switched single-particle interferometry and only position
measurements. We apply time-dependent scattering theory to determine the detrimental effect of dispersion. The proposed setup
brings into reach the possibility of establishing nonclassical correlations with respect to system properties that are truly
macroscopically distinct. 相似文献
7.
Yong-Chang Huang Leng Liao Xie-Guo Lee 《The European Physical Journal C - Particles and Fields》2009,60(3):481-487
We generalize the Faddeev–Jackiw canonical path integral quantization for the scenario of a Jacobian with J=1 to that for the general scenario of non-unit Jacobian, give the representation of the quantum transition amplitude with
symplectic variables and obtain the generating functionals of the Green function and connected Green function. We deduce the
unified expression of the symplectic field variable functions in terms of the Green function or the connected Green function
with external sources. Furthermore, we generally get generating functionals of the general proper vertices of any n-points
cases under the conditions of considering and not considering Grassmann variables, respectively; they are regular and are
the simplest forms relative to the usual field theory. 相似文献
8.
S. V. Kukhlevsky 《Applied physics. B, Lasers and optics》2008,93(1):145-150
Recently, we have shown a mechanism that could provide great resonant and nonresonant transmission enhancements of the classical
(nonquantum) light waves passed through subwavelength aperture arrays in thin metal films not by the plasmon–polariton waves,
but by the constructive interference of diffracted waves (beams generated by the apertures) at the detector placed in the
far-field zone. We now present a quantum reformulation of the model. The Hamiltonian describing the phenomenon of interference-induced
enhancement and suppression of both the intensity and energy of a quantum optical field is derived. The basic properties of
the field energy determining by the Hamiltonian are analyzed. Normally, the interference (addition) of two or more waves causes
enhancement or suppression of the light intensity, but not the light energy. The model shows that the phenomenon could be
observed experimentally, for instance, by using a subwavelength array of the coherent quantum light-sources (one- and two-dimensional
subwavelength apertures, fibers, dipoles, and atoms). 相似文献
9.
R. Bock K. G. R. Doss H. H. Gutbrod K. -H. Kampert B. Kolb I. Lund H. R. Schmidt T. Siemiarczuk W. Wiślicki 《Zeitschrift für Physik A Hadrons and Nuclei》1992,343(3):293-299
We report transverse,R
T
, and longitudinal,R
L
, source sizes extracted from two-pion interferometry analysis in the Au+Au and Nb + Nb interactions at 650 A MeV. For the Nb+Nb interactions, both,R
T
andR
L
, do not exceed the niobium nucleus radius. In the case of Au+Au collisions, the transverse size is larger than the longitudinal one being about 12 fm for the selection ofP
+ < 120=" mev/c.=" we=" also=" corroborate=" the=" existence=" of=" the=" previously=" reported=" specific=" three-pion=">One of us (T.S.) wishes to thank Professor M.I. Podgoretsky and Professor R.M. Weiner for interesting discussions and comments. We also wish to acknowledge remarks of Dr. B. Lörstad. 相似文献
10.
A. Miffre M. Jacquey M. Büchner G. Trénec J. Vigué 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,38(2):353-365
Using an atom interferometer, we have measured the static electric
polarizability of 7Li α=(24.33 ±0.16)×10-30
m3 = 164.2±1.1 atomic units with a 0.66% uncertainty. Our experiment, which is similar to an experiment done on sodium in 1995
by Pritchard and co-workers, consists in
applying an electric field on one of the two interfering beams and measuring the resulting phase-shift. With respect to Pritchard's
experiment, we have made several improvements which
are described in detail in this paper: the capacitor design is such that the electric field can be calculated analytically;
the phase sensitivity of our interferometer is substantially better,
near 16 mrad/
; finally our interferometer is species selective so that impurities present in our atomic beam (other alkali atoms or lithium
dimers) do not perturb our
measurement. The extreme sensitivity of atom interferometry is well illustrated by our experiment: our measurement amounts
to measuring a slight increase Δv of the atom velocity v
when it enters the electric field region and our present sensitivity is sufficient to detect a variation Δv/v ≈6 ×10-13. 相似文献
11.
Stefano De Leo Pietro Rotelli 《The European Physical Journal C - Particles and Fields》2009,62(4):793-797
We develop the potential scattering of a spinor within the context of perturbation field theory. As an application, we reproduce,
up to second order in the potential, the diffusion results for a potential barrier of quantum mechanics. An immediate consequence
is a simple generalization to arbitrary potential forms, a feature not possible in quantum mechanics. 相似文献
12.
Saurabh Gupta R. P. Malik 《The European Physical Journal C - Particles and Fields》2008,58(3):517-529
We demonstrate that the four-dimensional (4D) ((3+1)-dimensional) free Abelian 2-form gauge theory presents a tractable field-theoretical
model for the Hodge theory where the well-defined symmetry transformations correspond to the de Rham cohomological operators
of differential geometry. The conserved charges, corresponding to the above continuous symmetry transformations, obey an algebra
that is reminiscent of the algebra obeyed by the cohomological operators. The discrete symmetry transformation of the theory
represents the realization of the Hodge duality operation that exists in the relationship between the exterior and co-exterior
derivatives of differential geometry. Thus, we provide the realizations of all the mathematical quantities, associated with
the de Rham cohomological operators, in the language of the symmetries of the present 4D free Abelian 2-form gauge theory. 相似文献
13.
E. Schwarzberg G. Berkovic G. Marowsky 《Applied Physics A: Materials Science & Processing》1994,59(6):631-637
Direct measurement of the phase of the surface nonlinear susceptibility is based on the interference of nonlinear optical signals. Up to now, this has not been possible for Second-Harmonic Generation (SHG) in geometries such as Total Internal Reflection (TIR) due to the refractive dispersion of harmonic and fundamental light created in TIR. We demonstrate two schemes which enable us to overcome this dispersion, leading to interference between two second-harmonic signals generated consecutively by the same laser. The advantages and limitations of the two approaches are discussed. We use this technique to check the theoretical predictions for the nonlinear Fresnel factors for SHG in the TIR geometry.Paper presented at the 129th HE-Heraeus-Seminar on Surface Studies by Nonlinear Laser Spectroscopies, Kassel, Germany, May 30 to June 1, 1994 相似文献
14.
R. P. Malik 《The European Physical Journal C - Particles and Fields》2009,60(3):457-470
We derive the off-shell nilpotent Becchi–Rouet–Stora–Tyutin (BRST) and anti-BRST symmetry transformations for all the fields of a free Abelian 2-form gauge theory by exploiting the geometrical superfield approach to the BRST formalism.
The above four (3+1)-dimensional (4D) theory is considered on a (4, 2)-dimensional supermanifold parameterized by the four
even spacetime variables x
μ
(with μ=0,1,2,3) and a pair of odd Grassmannian variables θ and
(with
). One of the salient features of our present investigation is that the above nilpotent (anti-) BRST symmetry transformations
turn out to be absolutely anticommuting due to the presence of a Curci–Ferrari (CF) type of restriction. The latter condition emerges due to the application
of our present superfield formalism. The actual CF condition, as is well known, is the hallmark of a 4D non-Abelian 1-form
gauge theory. We demonstrate that our present 4D Abelian 2-form gauge theory imbibes some of the key signatures of the 4D
non-Abelian 1-form gauge theory. We briefly comment on the generalization of our superfield approach to the case of Abelian
3-form gauge theory in four, (3+1), dimensions of spacetime. 相似文献
15.
B. Viaris de Lesegno J.C. Karam M. Boustimi F. Perales C. Mainos J. Reinhardt J. Baudon V. Bocvarski D. Grancharova F. Pereira Dos Santos T. Durt H. Haberland J. Robert 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,23(1):25-34
A new Stern Gerlach interferometer operating with a nozzle beam of metastable argon atoms Ar* (3p5 4s, 3
P
2) is described. The selection of incoming (polarisation) and outgoing (analysis) Zeeman sublevels is achieved by use of laser
induced transitions at two wavelengths, 811.5 nm (closed J = 2 → J = 3 transition) and 801.5 nm (open J = 2 → J = 2 transition). Linear superpositions of Zeeman sublevels, just beyond the polariser and just before the analyser, are prepared
by means of two zones where Majorana transitions take place. In between, a controlled magnetic field configuration (the phase
object) is produced within a triple μ-metal shielding. Standard interference patterns are obtained by scanning the field and
detecting the atoms by secondary electron emission from a Faraday cup. When a static radial magnetic gradient is used, the
beam profile is modulated by interference. The transverse pattern, which can be translated at will by adding a homogeneous
field, is observed for the first time using a multi-channel electron multiplier followed by a phosphor screen and a CCD camera.
The results satisfactorily agree with all theoretical predictions.
Received 27 June 2002 / Received in final form 20 September 2002 Published online 4 February 2003
RID="a"
ID="a"e-mail: perales@lpl.univ-paris13.fr
RID="b"
ID="b"UMR 7538 du CNRS 相似文献
16.
We present a novel interferometric setup operating in the XUV spectral range. The interferometer consists of a combination
of a double pinhole (similar to Young’s double slit) and a transmission grating. In the case of a light source consisting
of discrete spectral lines, it allows recording interferograms for multi-colors simultaneously. We present two experiments
in which high-order harmonics generated by a titanium sapphire laser were used as the light source for the interferometer.
First, the temporal coherence lengths of the single harmonics were determined, and second, the index of refraction and the
absorption of a thin beryllium foil were measured simultaneously in the range of 17–25 nm. 相似文献
17.
S. A. Bass C. Hartnack H. Stöcker W. Greiner 《Zeitschrift für Physik A Hadrons and Nuclei》1995,352(2):171-174
We present a microscopic calculation of neutronsqueeze-out in relativistic heavy ion collisions at beam energies betweeen 400 and 1000 MeV/nucleon. After demonstrating the importance of the correct isospin treatment for the neutron to proton ratio, our main emphasis is put on the investigation of the properties of neutronsqueeze-out. Thesqueeze-out ratio increases monotonously with the transverse momentum of the neutrons. This ratio is independent of the incident beam energy if plotted versusp
t
/p
proj
. Most importantly, we observe a strong dependence on the nuclear equation of state and momentum dependent interaction.Supported by GSI, BMFT and DFG 相似文献
18.
The measurement of fast protons and neutrons emitted after antiproton annihilation at rest on238U and63Cu reveals a large neutron/proton ratioR. Its value for63Cu is larger than expected from the conventional model of intranuclear pion rescattering. A value ofR essentially constant over the whole range of mass number, from12C up to238U, is also announced by the experimentalists. It is shown that, on the contrary, the conventional scheme predicts a regular increase ofR with mass number. Alternative explanations of the effect are looked for. Within the usual scheme, an excess of negative pions, leading to more emitted neutrons, is not compatible with final pion multiplicities. The influence of meson resonances on the neutron/proton ratio is considered, as well as the possible occurrence of annihilations on two nucleons. They cannot warrant an increase ofR at low mass targets sufficient to explain a constant value over the whole range of target masses. 相似文献
19.
J. Kobayashi Y. Izumi K. Enomoto M. Kumakura Y. Takahashi 《Applied physics. B, Lasers and optics》2009,95(1):37-42
We have performed two-photon photoassociation experiments in atomic Bose–Einstein condensate (BEC) of 87Rb with spin degree of freedom which is created by all-optical method with CO2 lasers. The spinor character of the molecules has been revealed by the photoassociation spectrum with a new structure. The
hyperfine structure of the molecules near the dissociation limit is identified by observations of the Zeeman and AC-Stark
effects of the molecules. The molecules have been spin-selectively probed by the use of the light shift. This result would
open the new possibility of research on novel spinor molecular BEC. 相似文献
20.
Stefan Gmuca 《Zeitschrift für Physik A Hadrons and Nuclei》1992,342(4):387-392
The results of the modern relativistic Dirac-Brueckner calculations of nuclear matter are parametrized in terms of the relativistic- mean-field theory with scalar and vector nonlinear selfinteractions. It is shown that the inclusion of the isoscalar vector-meson quartic selfinteraction is essential for obtaining a proper density dependence of the vector potential in the mean-field model. The obtained mean-field parameters represent a simple parametrization of effective interaction in nuclear matter. This interaction may be used in the mean-field studies of the structure of finite nuclei without the introduction of additional free parameters.This work was supported in part by the Grant Agency of the Slovak Academy of Sciences under Grant No. GA SAV-517/1991. 相似文献