Quantum Depletion in Pairs and Thermal Depletion

• Authors: I. Chelagat , K. M. Khanna , J. K. Tonui , K. M. Muguro
• Languages of publication: EN

Abstracts

EN

For ultra-cold atoms, thermal depletion creates the BEC from the normal component, whereas quantum depletion ejects atoms from the BEC via interactions. Strong interactions in the Zero-Momentum State promote coherent quantum state transitions. As a result of quantum fluctuations, the particles will leave the ZMS (k=0) and occupy states above ZMS (k>0). This is quantum depletion. Quasi-particles with k>0 are described by the Hamiltonian using the pairs of creation and annihilation operators which correspond to the excitations of pairs of particles. Using Bogoliubov theory, it can be shown that it’s possible for particles to leave the ZMS in pairs and move to states with k>0. If ZMS exists at finite temperature, there will be thermal depletion.

Keywords

EN

Pair depletion; Quantum depletion; Thermal depletion; Zero Momentum State

Discipline

• PHYSICS: PHYSICS

• Publisher: Scientific Publishing House „DARWIN”
• Journal: World Scientific News
• Year: 2022
• Volume: 164
• Pages: 139-149

Contributors

author

I. Chelagat

• Department of Physics, University of Eldoret, P.O Box 1125-30100, Eldoret, Kenya

author

K. M. Khanna

• Department of Physics, University of Eldoret, P.O Box 1125-30100, Eldoret, Kenya

author

J. K. Tonui

• Department of Physics, University of Eldoret, P.O Box 1125-30100, Eldoret, Kenya

author

K. M. Muguro

• Department of Physics, University of Eldoret, P.O Box 1125-30100, Eldoret, Kenya

References

• [1] Anderson, M. H., Ensher, J. R., Matthews, M. R., Wieman, C. E., & Cornell, E. A. (1995). Observation of Bose-Einstein condensation in a dilute atomic vapor. Science, 269(5221), 198-201
• [2] W. Ketterle, Nobel lecture: when atoms behave as waves: Bose-Einstein condensation and the atom laser. Rev. Mod. Phys. 74 (2002), 1131–1151
• [3] Cornell, E. A., & Wieman, C. E. (2002). Bose-Einstein condensation in a dilute gas: the first 70 years and some recent experiments. International Journal of Modern Physics B, 16(30), 4503-4536
• [4] Sokol. L.P. (1995). Bose-Einstein Condensation in Liquid Helium (He). Cambridge University Press, Cambridge, 51
• [5] Cornell, E. A., & Wieman, C. E. (2002). Nobel Lecture: Bose-Einstein condensation in a dilute gas, the first 70 years and some recent experiments. Reviews of Modern Physics, 74(3), 875
• [6] Bradley, C. C., Sackett, C. A., Tollett, J. J., & Hulet, R. G. (1995). Evidence of Bose-Einstein condensation in an atomic gas with attractive interactions. Physical Review Letters, 75(9), 1687
• [7] Davis, K. B., Mewes, M. O., Andrews, M. R., van Druten, N. J., Durfee, D. S., Kurn, D. M., & Ketterle, W. (1995). Bose-Einstein condensation in a gas of sodium atoms. Physical Review Letters, 75(22), 3969
• [8] Klears. J., Schmitt J., Vewinger F., and Weitz M. (2010). Bose-Einstein Condensation of Photons in an Optical Microcavity. Nature 468 (7323): 545-548
• [9] Chang, R., Bouton, Q., Cayla, H., Qu, C., Aspect, A., Westbrook, C. I., & Clément, D. (2016). Momentum-resolved observation of thermal and quantum depletion in a Bose gas. Physical Review Letters, 117(23), 235303
• [10] Muler, C.A and Gaul, C. (2012). Condensate defarmation and quantum depletion of Bose-Einstein condensates in external potentials. New. J. Phys. 14, 075025
• [11] Huang K., (1966). Statistical mechanics. Wiley, London.
• [12] Mahan.G.D. Many particle physics, (2000). Plenum publishers, New York, 682.
• [13] Khanna, K.M. (1986). Statistical mechanics and many body problems. To-day and To-morrow primary and publishers. New Delhi, India, 158-164, 137.
• [14] Syvokon, V. E. (2006). Influence of the superfluid transition on the adsorption of thin helium films. Low Temperature Physics, 32(1), 48-54
• [15] Song, P. T. (2020). On the Bogoliubov theory: Casimir effect in a single weakly interacting Bose gas at zero-temperature with Neumann boundary condition. arXiv preprint arXiv:2006.11596
• [16] Khanna K.M. and Mehrotra S. N. Three-level approximation for interacting Boson transition-temperature calculation. Physica A: Statistical Mechanics and its Applications, Volume 81, Issue 2, p. 311-317, 1975
• [17] Pitaevskii, L., Stringari, S. Uncertainty principle, quantum fluctuations, and broken symmetries. J Low Temp Phys 85, 377–388 (1991)
• [18] Ohashi.Y and Griffin A. (2003). Superfluidity and collective modes in a uniform gas of Fermi atoms with Feshbach resonance. Phys.Rev.A67063612.
• [19] Minkiewiez V.J and Kitchen S. (1968). The phonom spectrum of HCP He-4. Phys. Rev. 174(1) 267-275
• [20] Pieczarka, M., Estrecho, E., Boozarjmehr, M., Bleu, O., Steger, M., West, K., ... & Ostrovskaya, E. A. (2020). Observation of quantum depletion in a non-equilibrium exciton–polariton condensate. Nature Communications, 11(1), 1-7

• Document Type: article