Coherent atomic matter waves

S. Inouye, Tilman Pfau, Subhadeep Gupta +4 more

Arnaud Landragin, Philippe Bouyer

S. Inouye, Pfau, Subhadeep Gupta +4 more

Mikio Kozuma, Yoichi Suzuki, Yoshio Torii +4 more

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.

S. Inouye, Tilman Pfau, Subhadeep Gupta +4 more

Summary form only given. Atomic matter waves, just like electromagnetic waves, can be focused, reflected, guided and split by the passive atom optical elements of today. However, the key for many applications of RF and light waves lies in the availability of amplifiers. Here, we report the observation of phase coherent amplification of atomic matter waves.

Shu Nagata, Tadej Mežnaršič, Chuixin Kong +1 more

Chemical reactions in a statistical ensemble are conventionally regarded as incoherent processes driven by thermodynamics. In the quantum degenerate regime, where atoms and molecules form coherent matter waves, reactions are theoretically described by nonlinear mixing of matter-wave fields. In this scenario, we expect phase matching between reactants and products, analogous to the mixing of photonic fields in nonlinear optics. Here we report on the observation of phase coherent reaction dynamics of Bose-condensed atoms and molecules near a Feshbach resonance. Using matter-wave diffraction with optical lattices, we verify spatial coherence of both atoms and molecules and observe phase doubling when atomic waves combine into molecular waves, the matter-wave analogue of optical frequency doubling. The diffraction patterns further reveal two-atom entanglement generated during the reaction. Our observations establish phase coherence and entanglement generation as two essential features of "quantum many-body chemistry". Moreover, our work opens a pathway to control of reaction dynamics by manipulation of matter-wave phases.