Robust Entanglement for Multiple Trapped Ions in Thermal Motion

Abstract

A robust scheme is proposed for producing maximally entangled states formany trapped ions in thermal motion. In the scheme the ions aresimultaneously illuminated by two standing-wave laser fields. During theoperation the phases of the lasers are inverted, which not only cancels thevibration-dependent parts in the evolution operator, but also suppressesdirect off-resonant coupling of the internal states. Thus, our scheme allowsthe production of entanglement for hot trapped ions with laser fields ofhigh intensity, which makes the entanglement speed extremely high.