Controlling spin dynamics in a one-dimensional quantum gas

Andrea Micheli, P. Zoller

We propose a scheme utilizing quantum interference to control the transport of atoms in a one-dimensional optical lattice by a single impurity atom. The two internal state of the impurity represent a spin-$1∕2$ (qubit), which in one spin state is perfectly transparent to the lattice gas, and in the other spin state acts as a single atom mirror, confining the lattice gas. This allows one to ``amplify'' the state of the qubit, and provides a single-shot quantum nondemolition measurement of the state of the qubit. We derive exact analytical expression for the scattering of a single atom by the impurity, and give approximate expressions for the dynamics of a gas of many interacting bosonic or fermionic atoms.

M. S. Makivić, Mark Jarrell

Dmitry Mozyrsky, Alexander Dementsov, Vladimir Privman A

We develop a unified theoretical description of the induced interaction and quantum noise in a system of two spins (qubits) coupled via a quasi-one-dimensional electron gas in the Luttinger liquid regime. Our results allow evaluation of the degree of coherence in quantum dynamics driven by the induced indirect exchange interaction of localized magnetic moments due to conduction electrons, in channel geometries recently experimentally studied for qubit control and measurement.

K. Katsumata

S. Whitlock, Philipp Wicke, N. J. van Druten

We show a new way to tune interactions in one-dimensional quantum gases using state-dependent dressed potentials, enabling control over non-equilibrium spin motion in a two-component gas.

Benjamin Land, Christopher D. Hamley, Corey Gerving +3 more