© 2026 Aqora Quantum S.A.S.

Terms Privacy Legal Notice

Laser Physics Letters

Atom interferometer using two Stern-Gerlach magnets

Kenneth H. Rubin, M. Eminyan, F Perales, Renaud Mathevet, K. Brodsky, B. Viaris de Lesegno, J. Reinhardt, M. Boustimi, J. Baudon, J.‐C. Karam, Jacques Robert

Published Mar 9, 2004• 12 citations

Abstract

An atom interferometer using two Stern-Gerlach magnets as polariser and analyser is described. The interferometer was first operated with a thermal beam of ground state potassium atoms. In that case the beam splitters are two radio-frequency zones within a transverse homogeneous magnetic field building a coherent superposition of Zeeman states. Ramsey fringes are obtained by scanning the RF-frequency through the resonance profile. Pulsing the RF power allows to get the time-of-flight distribution of the beam. Atomic interference fringes (``Stern-Gerlach fringes'') are observed when the magnitude of an inhomogeneous magnetic field located in between the beam splitters is scanned. When the inhomogeneous field is also pulsed, the scalar Bohm-Aharonov effect is observed. The use of metastable helium atoms (He*23S) in place of potassium atoms is proposed. In addition to the usual advantages provided by metastable atoms of high internal energy, this atom offers the specific advantage to behave as an ideal spin-one particle. This allows us to greatly simplify the polarisation scheme of the interferometer. Possible applications involving transversally inhomogeneous magnetic fields are given and limitations due to the finite source size and angular aperture are discussed.

DOI: 10.1002/lapl.200310047

Related papers

Double atom interferometer

Renaud Mathevet, K. Brodsky, J. Baudon +4 more

A double atom interferometer based upon the Stern-Gerlach method in which the first interferometer acts as a ``nonordinary'' source for the second one is described. Experiments have been carried out with a wide-velocity-distribution beam of metastable hydrogen atoms, using two different operating modes: (i) continuous mode in which the magnitude of the magnetic field in the first interferometer is fixed whereas that of the second one is scanned; (ii) time-of-flight mode in which both magnetic fields are fixed. In the former case lateral interference patterns appear, in the latter one an overmodulation of the time-of-flight distribution is observed. It is predicted that this overmodulation becomes more and more marked as the number of interferometers is increased, leading to a limiting behavior characteristic of a quantum Zeno effect.

Physical Review A•Nov 1, 1998•5 citations

Polarisation measurement of a He(23Si1) atomic beam

J Giroux, Robby Lapointe, R.J. Slobodrian

An atomic beam of He in the metastable 2 3 S 1 state can be atomic-spin-polarised by Stern-Gerlach selection using a sextupole magnet. The authors report the first measurements of the polarisation obtained by this method. The authors have determined the metastable beam velocity distribution from a time-of-flight measurement. The distribution was found to be in the range of thermal velocities. The selection efficiency of the sextupole magnet was studied using a Stern-Gerlach deflection with an inhomogeneous dipole field. The experimental results give a vector polarisation close to 95%. Thus, the technique can be useful for many applications.

Journal of Physics E Scientific Instruments•Nov 1, 1984•1 citation

Nanometer scale period sinusoidal atom gratings produced by a Stern-Gerlach beam splitter

B. Dubetsky, Georg A. Raithel

An atom interferometer based on a Stern-Gerlach beam splitter is proposed. Atom scattering from a combination of magnetic quadrupole and homogeneous magnetic fields is considered. Using Raman transitions, atoms are coherently excited into and de-excited from sublevels having nonzero magnetic quantum numbers. The spatial regions in which the atoms are in such sublevels are small and have magnetic fields designed to have constant gradients. Therefore, the atoms experience position-independent accelerations, and the aberration of the coherently separated and recombined atomic beams remains small. We find that because of these properties it is possible to envision an apparatus producing atomic density gratings with nm-scale periods and large contrasts over 10-100 $μ$m. We use a new method of describing the atomic interaction with a pulsed spatially homogeneous field. In our detailed analysis, we calculate corrections caused by the non-linear part of the potential and the finite value of the de-Broglie wave length. The chromatic aberration and the effects of an angular beam divergence are analyzed, and optimal conditions for an experimental demonstration of the technique are identified.%The $lin\bot %lin$ combination of resonant co-propagating traveling waves splits %atoms between different Zeeman sublevels. %For a given desirable atom %grating period and length, characteristics of the atomic beam and %magnetic field are found from requirements that corrections remain %below $10%.$

arXiv:physics/0206029•Jun 11, 2002•1 citation

Atomic Stern-Gerlach interferences with time-dependent magnetic fields

Síle Nic Chormaic, Christian Miniatura, O. Gorceix +7 more

In atomic Stern-Gerlach (polarization) interferometry with time-dependent magnetic fields both the spatial and temporal parts of the atomic phase are generally affected. This leads to a total energy shift and to an inelastic momentum transfer. Some of the related effects are studied using a beam of metastable hydrogen atoms. In particular the scalar Aharonov-Bohm effect and its nondispersivity are considered, in addition to other phase shift effects occurring where the field gradient differs from zero.

Physical Review Letters•Jan 3, 1994•40 citations

Atomic Interferometry with Metastable Hydrogen Atoms

Jacques Robert, Christian Miniatura, S. Le Boiteux +3 more

An atomic interferometer using the longitudinal Stern-Gerlach effect has been constructed. A thermal beam of metastable hydrogen atoms has been used to test the apparatus. Interference patterns have been obtained. The visibility of the fringes is limited by the velocity spread of the beam. The observed patterns are in good agreement with that predicted from the actual velocity distribution.

Europhysics Letters (EPL)•Sep 1, 1991•47 citations

Atomic spatial coherence monitoring and engineering with magnetic fields

O. Gorceix, É. Maréchal, T. Miossec +4 more

Summary form only given. Spatial coherences are measured by means of a new atom interferometry technique. First, a coherent superposition of the Zeeman components of the atom is built by means of well-controlled magnetic interactions. Second, pulsed inhomogeneous magnetic fields are employed to coherently separate and reunite the atomic substates via the Stern-Gerlach induced forces. Finally, atomic interference fringes are recorded on the state-selected outcoming sample by changing the spatial separation. This method bears strong similarities with the Fourier-transform spectroscopy of light. The interferogram visibility curve yields the atom sample spatial coherences. For example, when the applied magnetic gradients are parallel to the atom trajectory, one gets the coherence length by varying the overlap of the separated wavepackets. Several experiments on cold cesium atoms have been performed and are presented. Furthermore, we have used our magnetic cooling method to prepare the atom cloud upstream from the interferometer. Large enhancements of the coherence length are demonstrated.

Conference on Lasers and Electro-Optics•Aug 29, 2005•0 citations

An atom interferometer using two Stern-Gerlach magnets as polariser and analyser is described. The interferometer was first operated with a thermal beam of ground state potassium atoms. In that case the beam splitters are two radio-frequency zones within a transverse homogeneous magnetic field building a coherent superposition of Zeeman states. Ramsey fringes are obtained by scanning the RF-frequency through the resonance profile. Pulsing the RF power allows to get the time-of-flight distribution of the beam. Atomic interference fringes (``Stern-Gerlach fringes'') are observed when the magnitude of an inhomogeneous magnetic field located in between the beam splitters is scanned. When the inhomogeneous field is also pulsed, the scalar Bohm-Aharonov effect is observed. The use of metastable helium atoms (He*23S) in place of potassium atoms is proposed. In addition to the usual advantages provided by metastable atoms of high internal energy, this atom offers the specific advantage to behave as an ideal spin-one particle. This allows us to greatly simplify the polarisation scheme of the interferometer. Possible applications involving transversally inhomogeneous magnetic fields are given and limitations due to the finite source size and angular aperture are discussed.

A double atom interferometer based upon the Stern-Gerlach method in which the first interferometer acts as a ``nonordinary'' source for the second one is described. Experiments have been carried out with a wide-velocity-distribution beam of metastable hydrogen atoms, using two different operating modes: (i) continuous mode in which the magnitude of the magnetic field in the first interferometer is fixed whereas that of the second one is scanned; (ii) time-of-flight mode in which both magnetic fields are fixed. In the former case lateral interference patterns appear, in the latter one an overmodulation of the time-of-flight distribution is observed. It is predicted that this overmodulation becomes more and more marked as the number of interferometers is increased, leading to a limiting behavior characteristic of a quantum Zeno effect.

An atomic beam of He in the metastable 2 3 S 1 state can be atomic-spin-polarised by Stern-Gerlach selection using a sextupole magnet. The authors report the first measurements of the polarisation obtained by this method. The authors have determined the metastable beam velocity distribution from a time-of-flight measurement. The distribution was found to be in the range of thermal velocities. The selection efficiency of the sextupole magnet was studied using a Stern-Gerlach deflection with an inhomogeneous dipole field. The experimental results give a vector polarisation close to 95%. Thus, the technique can be useful for many applications.

An atom interferometer based on a Stern-Gerlach beam splitter is proposed. Atom scattering from a combination of magnetic quadrupole and homogeneous magnetic fields is considered. Using Raman transitions, atoms are coherently excited into and de-excited from sublevels having nonzero magnetic quantum numbers. The spatial regions in which the atoms are in such sublevels are small and have magnetic fields designed to have constant gradients. Therefore, the atoms experience position-independent accelerations, and the aberration of the coherently separated and recombined atomic beams remains small. We find that because of these properties it is possible to envision an apparatus producing atomic density gratings with nm-scale periods and large contrasts over 10-100

μ

m. We use a new method of describing the atomic interaction with a pulsed spatially homogeneous field. In our detailed analysis, we calculate corrections caused by the non-linear part of the potential and the finite value of the de-Broglie wave length. The chromatic aberration and the effects of an angular beam divergence are analyzed, and optimal conditions for an experimental demonstration of the technique are identified.%The

lin\bot %lin

combination of resonant co-propagating traveling waves splits %atoms between different Zeeman sublevels. %For a given desirable atom %grating period and length, characteristics of the atomic beam and %magnetic field are found from requirements that corrections remain %below

10%.

In atomic Stern-Gerlach (polarization) interferometry with time-dependent magnetic fields both the spatial and temporal parts of the atomic phase are generally affected. This leads to a total energy shift and to an inelastic momentum transfer. Some of the related effects are studied using a beam of metastable hydrogen atoms. In particular the scalar Aharonov-Bohm effect and its nondispersivity are considered, in addition to other phase shift effects occurring where the field gradient differs from zero.

Summary form only given. Spatial coherences are measured by means of a new atom interferometry technique. First, a coherent superposition of the Zeeman components of the atom is built by means of well-controlled magnetic interactions. Second, pulsed inhomogeneous magnetic fields are employed to coherently separate and reunite the atomic substates via the Stern-Gerlach induced forces. Finally, atomic interference fringes are recorded on the state-selected outcoming sample by changing the spatial separation. This method bears strong similarities with the Fourier-transform spectroscopy of light. The interferogram visibility curve yields the atom sample spatial coherences. For example, when the applied magnetic gradients are parallel to the atom trajectory, one gets the coherence length by varying the overlap of the separated wavepackets. Several experiments on cold cesium atoms have been performed and are presented. Furthermore, we have used our magnetic cooling method to prepare the atom cloud upstream from the interferometer. Large enhancements of the coherence length are demonstrated.