Chinese Journal of Physics

A Theoretical Investigation of Low-Dimensional Bose-Einstein Condensations

Ching‐Fuh Lin

Published Apr 1, 2006• 0 citations

Abstract

Low-dimensional Bose-Einstein condensations (BEC) for g(e) (the density of states) = Cde(superscript d-1) with d ≤ 1, corresponding to a dimensionality of not larger than 2, are theoretically analyzed. When the energy quantization of the first excited state is taken into account, the boson number in the excited states is finite even for d ≤ 1 with the density of states remaining proportional toe(superscript d-1). The condensation temperature increases with the particle number faster for d ≤ 1 than for d ＞ 1. The condensation depends highly on the quantized energye1 of the first excited state. Whene1 just deviates slightly from zero, the condensation temperature quickly increases withe1. Theoretical estimation shows that a low-dimensional BEC can occur at a temperature above 1 K for excitons in semiconductor quantum wells even without the harmonic-oscillator potential.

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