Stochastization of long living spin-cyclotron excitations in a spin-unpolarised quantum Hall system
S. Dickmann, B. D. Kaysin
Institute of Solid State Physics, Russian Academy of Sciences, 142432 Chernogolovka, Russia
Abstract
In the present study we address the kinetics of long-lived excitations
at zero temperature in an electronic quantum Hall system with filling
factor ν=2. The initial coherent state of spin-cyclotron
magnetoexitons with two-dimensional wave vector q=0 resulting
from laser pumping is stochastized over time due to emission of acoustic
phonons. The elementary emission process requires participation of two
magnetoexitons, so the effective rate of phonon emission is proportional
to the excitation density squared, and the stochastization process occurs
nonexponentially with time. The final distribution of magnetoexitons over
2D momenta, established as a result of stochastization, is compared with
equilibrium distribution at finite temperature.