“Stability Signature” in Two-Species Dilute Bose-Einstein Condensates

Abstract

We identify an eigenvalue associated with a dilute two-species Bose-Einstein condensate as the determiner of condensate stability. It plays the same role as the sign of scattering length in a one-species condensate. We predict that there is a range of interspecies interaction strength in which a sodium-rubidium mixture can be stable in a harmonic trap. {copyright} {ital 1997} {ital The American Physical Society}