Nonlinear resonances and the melting of Wigner crystals in a Paul trap.

Abstract

This article discussed the melting of ``crystals'' of two laser-cooled ions in a Paul trap. It presents computer simulations which reproduce melting at some realistic trap parameters in a model which includes laser-ion interaction but no collisions with residual gas molecules, highlighting the importance of spontaneous-emission fluctuations. Crystal fragility at certain trap voltages coincides with low-order nonlinear resonances, an aspect not mentioned in earlier discussions of the system.