title: [Magnetic-field-induced nonthermal occupation of higher subbands in a three-barrier tunneling structure].
abstract: When injected electrons in a quantum well first experience an intersubband relaxation process before their escaping by tunneling through a double-barrier structure behind, the magnetic suppression of intersubband LO or LA phonon scattering can give rise to a noticeable nonthermal occupation in higher-lying subbands. That is clearly verified by the relative intensity ratio of the interband photoluminescence spectra for E2-HH1 and E1-HH1 transitions. The observed phenomenon may provide an effective method for controlling intersubband scattering rate, a central issue in so-called quantum cascade lasers, and facilitating the population inversion between subbands in quantum wells.
authors.affiliation: National Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.
authors.forename: Long
authors.initials: L
authors.lastname: An
authors.forename: Yan
authors.initials: Y
authors.lastname: Tang
authors.forename: Ji-dong
authors.initials: JD
authors.lastname: Zhang
authors.forename: Yang
authors.initials: Y
authors.lastname: Ji
authors.forename: Ping-heng
authors.initials: PH
authors.lastname: Tan
authors.forename: Fu-hua
authors.initials: FH
authors.lastname: Yang
authors.forename: Hou-zhi
authors.initials: HZ
authors.lastname: Zheng