Phase-sensitive detection for unconventional Bose-Einstein condensation

Abstract

We propose a phase-sensitive detection scheme to identify the unconventional ${p}_{x}\ifmmode\pm\else\textpm\fi{}i{p}_{y}$ symmetry of the condensate wave functions of bosons, which have already been proposed and realized in high bands in optical lattices. Using the impulsive Raman operation combined with time-of-flight imaging, the off-diagonal correlation functions in momentum space give rise to the relative phase information between different components of condensate wave functions. This scheme is robust against the interaction and interband effects, and provides evidence of unconventional Bose-Einstein condensations with nontrivial condensation symmetries.