MOBILITY OF ION IN A SYSTEM OF INTERACTING BOSE PARTICLES. Technical Report No. 5

Ryo Abe, Ko Aizu

Published Jan 1, 1960• 0 citations

Abstract

The transport property of an ion in a dilute Bose-Einstein gas subject to an external electric field is investigated through Boltzmann equation approach. By means of the Bogolyubov transformation, the interaction hamiltonian between ion and elementary excitation is obtained, and the cross section for the scattering of the ion from phonons or rotons is calculated. The solution to the Boltzmann equation is obtained by the use of a variation principle, and the temperature dependence of ion mobility is shown to be UPSILON /sup -4/ at very low temperature regions where phonon excitations are more important than rotons. At higher temperatures where roton excitations are important the temperature dependence is shown to be UPSILON /sup -1/ exp( DELTA /k UPSILON ), where DELTA is the excitation energy of roton. The agreement in absolute magnitude with the experimental data in liquid helium is obtained by choosing reasonable value of parameter both in higher and lower temperature regions. Comparison with the Khalatnikov and Zharkov theory is given, and also the ion mobility in Fermi system is briefly discussed. (auth)

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