Controlling spin dynamics in a one-dimensional quantum gas

Phil Wicke - January 04 2010

Abstract

Reducing the dimensionality of a system has dramatic consequences and
leads to remarkable new physics. In this regard, quantum gases offer
unique opportunities to address important open questions in quantum
many-body physics, by allowing full control over all relevant
parameters. We create coherent superpositions of both spin and motional
degrees of freedom and probe spin dynamics of a one-dimensional (1D)
Bose gas of 87Rb on an atom chip. We observe interaction driven focusing
of one spin component by mean field interaction with another component,
directly related to the effective 1D interaction strength. We
demonstrate experimental control over the 1D interaction strengths
through state-selective radio-frequency dressing. The focusing behaviour
is altered by tuning the transverse trapping potential in a
state-dependent way. This enables, for instance, access to the point of
spin-independent interactions where exact quantum many-body solutions
are available.