Instability and stratification of a two-component Bose-Einstein condensate in a trapped ultracold gas

摘要: The thermodynamic stability of a trapped Bose gas with two-component condensate, e.g., atoms in two distinct hyperfine states or binary gaseous mixture, is considered on the basis modified Gross-Pitaevskii equations. Under certain conditions system becomes unstable respect to stratification, i.e., spatial separation between condensates. One condensate assumes donutlike distribution, while other retains centered distribution. Possible applications theory recent experimental data overlapping condensates ${}^{87}$Rb are discussed.