摘要We consider the motion of an impurity in a Bose-Einstein condensate system at T=0K with the contact interactions for boson-boson and boson-impurity. Under the forward-scattering approximation, we obtain a Frohlich-like Hamiltonian for this system, which means that a polaron can be formed. The effective mass, the phonon number and the energy to form a polaron are obtained. We also discuss the validity of the forward-scattering approximation for this system.
Abstract：We consider the motion of an impurity in a Bose-Einstein condensate system at T=0K with the contact interactions for boson-boson and boson-impurity. Under the forward-scattering approximation, we obtain a Frohlich-like Hamiltonian for this system, which means that a polaron can be formed. The effective mass, the phonon number and the energy to form a polaron are obtained. We also discuss the validity of the forward-scattering approximation for this system.
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2009, Vol. 26 
