Bose-Einstein condensation in canonical ensemble with fixed total momentum

التفاصيل البيبلوغرافية
العنوان: Bose-Einstein condensation in canonical ensemble with fixed total momentum
المؤلفون: Plyashechnik, Andrey S., Sokolik, Alexey A., Lozovik, Yurii E.
المصدر: Phys. Rev. A 110, 013301 (2024)
سنة النشر: 2024
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Quantum Gases, Condensed Matter - Statistical Mechanics
الوصف: We consider Bose-Einstein condensation of noninteracting homogeneous three-dimensional gas in canonical ensemble when both particle number $N$ and total momentum $\mathbf{P}$ of all particles are fixed. Using the saddle point method, we derive the large-$N$ analytical approximations for partition function, free energy, and statistical distributions of occupation numbers of different single-particle energy levels. At temperatures below the critical point of phase transition, we predict, in some ranges of $\mathbf{P}$, fragmentation of the condensate, when more than one single-particle level is macroscopically occupied. The occupation number distributions have approximately Gaussian shapes for the levels hosting the condensate, and exponential shapes for other, noncondensate levels. Our analysis demonstrates breaking of Galilean invariance of moving finite-temperature many-particle system in the presence of Bose-Einstein condensation and extends the theory of moving and rotating quantum systems to the finite-temperature large-$N$ limit.
Comment: 15 pages, 8 figures; Section IV.B and Supplemental Material were added
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevA.110.013301
URL الوصول: http://arxiv.org/abs/2403.08482
رقم الأكسشن: edsarx.2403.08482
قاعدة البيانات: arXiv