Inversion of Zeeman splitting of exciton states in InGaAs quantum wells

Abstract

Zeeman splitting of the quantum confined states of excitons in the InGaAs quantum wells (QWs) is experimentally found to strongly depend on the quantization energy. Moreover, it changes its sign when the quantization energy increases with the decrease of the QW width. In the 87-nm QW, the sign change is observed for the excited quantum confined states, which are above the ground state only by a few meV. A two-step approach for the numerical solution of two-particle Schrödinger equation with taking into account for the Coulomb interaction and the valence-band coupling is used for theoretical justification of the observed phenomenon. The calculated variation of the g-factor convincingly follows the dependencies obtained in the experiments.

Exciton-polariton interference controlled by electric field

“…Several previous studies were devoted to the excitonic effects induced by linear-in-K terms. In particular, a K dependence of the exciton g factor [17][18][19], an increase of the exciton-light coupling in the longitudinal magnetic field directed along the heterostructure growth axis [20], and an increase of the exciton effective mass in a transverse magnetic field [21] are reported. In Refs.…”

“…is the electric field of the jth polaritonic wave and K j is its wave vector; Z is the exciton center-of-mass coordinate. The condition (19) means that the total excitonic contribution into the polarizability at the QW boundaries should be zero. Besides, the standard Maxwell's boundary conditions (MBC) at the QW interfaces are used.…”

“…The developed theory allows us to model the reflectance spectra of the heterostructure with the QW using Eqs. (1), (10), (17), (18), (19), and (20). The modification of the spectra by the electric field is described by the factor λ(F ) shown in the inset of Fig.…”

Энергия относительного движения электрона и дырки в экситоне во внешнем электрическом поле в пластине GaAs

“…Магнитное поле, приложенное в геометрии Фогта, приводит к эффективному увеличению массы экситона [23][24][25][26][27][28][29][30]. В геометрии Фарадея наблюдается эффект зависимости экситонного g-фактора от волнового вектора экситона [31][32][33][34][35].…”

Vanishing Zeeman energy in a two-dimensional hole gas

“…Measuring Zeeman splitting (ZS) of hole states under an external magnetic field has been central in probing hole spin properties, as it is directly related to the hole g factor, which is itself strongly influenced by the underlying SOI, strain, symmetry, and confinement [24,25]. In III-V semiconductors [24,[26][27][28][29][30][31][32][33][34][35][36][37][38], hole spin splitting depends nonlinearly on the out-of-plane magnetic field strength B, causing Landau level crossings and anticrossings [28,39] and Zeeman crossings and anticrossings [12,40,41]. The nonlinearity is usually modeled by a quadratic-in-field contribution to ZS [24], which owes its existence to valence band mixing.…”