Bump-on-tail instability of twisted excitations in rotating cold atomic clouds

Autor:	Rodrigues, J. D., Terças, H., Mendonça, J. T.
Rok vydání:	2015
Předmět:	Condensed Matter - Quantum Gases
Druh dokumentu:	Working Paper
DOI:	10.1209/0295-5075/113/13001
Popis:	We develop a kinetic theory for twisted density waves (phonons), carrying a finite amount of orbital angular momentum, in large magneto optical traps, where the collective processes due to the exchange of scattered photons are considered. Explicit expressions for the dispersion relation and for the kinetic (Landau) damping are derived and contributions from the orbital angular momentum are discussed. We show that for rotating clouds, exhibiting ring-shaped structures, phonons carrying orbital angular momentum can cross the instability threshold and grow out of noise, while the usual plane wave solutions are kinetically damped. Comment: 5 pages, 5 figures
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1508.05127 Zobrazit plný text záznamu View this record from Arxiv