Thermodynamics of Bose—Einstein Condensation

Dr. Ali Khan

The study of exotic states of matter, particularly superfluids and Bose-Einstein condensates (BECs), has revolutionized our understanding of quantum mechanics in macroscopic systems. This article explores the thermodynamic properties of these states, focusing on their unique behavior at ultra-low temperatures. Superfluids exhibit zero viscosity and anomalous flow characteristics, while Bose-Einstein condensates, formed by cooling bosons to near absolute zero, present quantum phenomena on a macroscopic scale. This paper reviews key thermodynamic concepts, such as entropy, heat capacity, and chemical potential, as they apply to these exotic phases. Additionally, the relationship between quantum coherence and thermodynamic stability in superfluids and BECs is examined, along with the practical implications for quantum technologies.

Adelchi Fabrocini

Joseph V Pulé, André F. Verbeure, Valentin Anatol'evich Zagrebnov

We study the effect of electromagnetic radiation on the condensate of a Bose gas. In an earlier paper we considered the problem for two simple models showing the cooperative effect between Bose-Einstein condensation and superradiance. In this paper we formalise the model suggested by Ketterle et al in which the Bose condensate particles have a two level structure. We present a soluble microscopic Dicke type model describing a thermodynamically stable system. We find the equilibrium states of the system and compute the thermodynamic functions giving explicit formulae expressing the cooperative effect between Bose-Einstein condensation and superradiance.

Hendrik B. G. Casimir

Tao Wen, Ji-Ping Ye, Su-Qiao An +3 more

Quantum confinement shifts quantum phase transitions like the λ-point of liquid helium. This effect is calculated here for ideal Bose–Einstein condensates (BECs) using thermodynamic mapping (TM). TM is a procedure to obtain low temperature behaviour from high temperature information via elementary transformations. We report here a series of TM relations for thermodynamic quantities and the resulting transition properties for ideal BECs.