Phase-Coherent Amplification of Matter Waves

Abstract

Phase-coherent matter-wave amplification was demonstrated using Bose- Einstein-condensed rubidium-87 atoms. A small seed matter wave was created with coherent optical Bragg diffraction. Amplification of this seed matter wave was achieved by using the initial condensate as a gain medium through the superradiance effect. The coherence properties of the amplified matter wave, studied with a matter-wave interferometer, were shown to be locked to those of the initial seed wave. The active matter-wave device demonstrated here has great potential in the fields of atom optics, atom lithography, and precision measurements.

Spinor Condensates and Light Scattering from Bose-Einstein Condensates

“…This might be due to a distortion of the matter wave during the amplification, but this effect requires further study. A similar experiment with rubidium atoms was done at the University of Tokyo [69]. This experiment can be regarded as a demonstration of an active atom interferometer.…”

Adiabatic and nonadiabatic merging of independent Bose-Einstein condensates

“…The prospect of the creation of a continuous, coherent atomic beam, the atomic analogy of laser beam, has been of great interest to many ever since the successful generation of Bose-Einstein condensate (BEC) [1,2,3,4,5,6,7,8]. One of the major challenges to such applications lies in the difficulty in continuous condensation of atomic gas due to stringent cooling conditions.…”

Mode competition in superradiant scattering of matter waves

“…Absorption of pumping photons and preferential scattering into so-called end-fire modes along the BEC's long axis lead to the observation of patterns of coherently recoiling atoms. Amplification of matter waves was further characterized with the use of an initial matter wave seed formed via Bragg diffraction of a Bose condensate and its coherence nature was demonstrated [2,3].For an elongated BEC, superradiant Rayleigh scattering light is emitted along the long axis because the gain for superradiance is maximum in this direction. However, different superradiant modes can be obtained when a matter wave seed with non-zero momentum is created before pumping since light can then be resonantly diffracted in a different direction [4].…”

“…Absorption of pumping photons and preferential scattering into so-called end-fire modes along the BEC's long axis lead to the observation of patterns of coherently recoiling atoms. Amplification of matter waves was further characterized with the use of an initial matter wave seed formed via Bragg diffraction of a Bose condensate and its coherence nature was demonstrated [2,3].…”

“…Analyzing superradiance with non common configurations is also important as combining early stage superradiance described with quantum theory and long timescale superradiance which is well captured within a semi-classical theory taking into account propagation effects is currently a topic of high interest [7,8] We present in this article an experimental analysis of mode competition in superradiance scattering. Rather than relying on an initial matter wave seed formed via Bragg diffraction of a BEC [2][3][4] our superradiance experiment is performed after initial adiabatic loading of a BEC along its long axis inside a 1D optical lattice [9]. The choice of contra propagating optical beams (wave vector ± k L ) for the optical lattice loading leads to the formation of a matter grating with period d = π/k L , so that three waves are mostly populated after release from the optical lattice (see Fig.…”