Magnetoluminesence of Ge/Ge_(1-x)Si_x multiple quantum well structures.

摘要

The luminesence spectra of Ge/Ge_(1-x)Si_x multiple quantum well structures at temperatures about 2K and magnetic field up to 14 T have been measured for the first time. The interest in magnetooptical investigations of these structures was called forth by type-I band edge modulation and indirect radiative transitions. The above facts allow to expect for low temperatures of electron-hole system in investigating structures and more simple obtaining of conditions for electron-hole system phase transition observation. The observed changes of exciton luminescence lines under magnetic field are explained on the basis of a theory which takes into account the mixing of hole levels in the magnetic field. The obtained data allow to evalluate the g-factors and lifetime of excitons in the investigated Ge/Ge_(1-x)Si_x structures.