Dependence of Electron g-Factor on Barrier Aluminum Content in GaAs/AlGaAs Quantum Wells

Abstract

The effects of quantum confinement on electron g-factor tensor components, g ? and g k , were investigated for a wide variety of GaAs/ Al x Ga 1Àx As quantum well structures, including the weak confinement regime, to determine the mapping of the g-factor components as functions of the aluminum content of an Al x Ga 1Àx As barrier and GaAs well thickness. The g-factor components were determined from the periods of electron spin precession, which were assessed by polarization-and time-resolved photoluminescence measurements under a magnetic field. The measured transverse component g ? was found to depend substantially on the barrier aluminum content, while the longitudinal component g k was insensitive to the aluminum content. In addition to the experiments, the electron g-factor was analyzed theoretically on the basis of the three-band kÁp perturbation theory by using Kiselev's method. Comparison of the experimental and theoretical results demonstrates that the three-band kÁp calculation is sufficient to reproduce the main features of the experimental results including the effects of the barrier aluminum content.

Optical detection of anisotropicg-factor and nuclear spin polarization in a single CdTe quantum well

“…Therefore, a lot of research effort has been put forth to understand better the interaction of carrier spins with each other [4][5][6] and with their environments such as tunable lasers 7) or barrier layers. 8) Thanks to the previous studies, the generation dynamics of RESP in semiconductors has been clarified except for the initial temporal region. 1,9) One of the remained obstacles for a longer spin coherence is the hyperfine interaction (HFI) between the photo-created carriers and the lattice nuclei, which recently has attracted a great attention especially in quantum dots (QDs).…”

Electrong-factor anisotropy in symmetric (110)-oriented GaAs quantum wells

“…3. The sign of the measured g-factor depends on the energy-dependence of g * [28][29][30] and on the penetra- tion of the wavefunction into the barrier material which has a positive g-factor. As a consequence g s increases monotonically with decreasing well width, i.e., increasing confinement energy.…”

Analysis of Electron Spin-Spin Interaction in Coupled Quantum Well

“…1 (b). The two peaks with emission photon energy of 1.545 and 1.530 eV correspond to the emission from electrons localized in 10 and 15 nm GaAs well, respectively [14]. Emission photon energies from CQW sample shown in Fig.…”

“…Electron spin in semiconductor nanostructures has been investigated for fundamental physics and expected to the candidate for quantum bit (qubit) for quantum information technologies [1,2]. The electron spin behavior in semiconductors can be measured precisely by spin precession measurements [3][4][5][6][7][8][9][10][11][12][13][14]. When the electron spin state localized in the semiconductor is considered to be a qubit, electron spin-spin interaction in semiconductors is important for control of qubit states in quantum logic gates [1,2].…”

“…When the electron spin state localized in the semiconductor is considered to be a qubit, electron spin-spin interaction in semiconductors is important for control of qubit states in quantum logic gates [1,2]. Since the spin-spin interaction effects are not able to be observed by conventional non-linear optical measurements [5-7, 10, 11, 13] and photoluminescence (PL) measurements [3,4,8,9,12,14], which show the total characteristics of large number of electron spins, there are few fundamental studies about the electron spin-spin interaction until now. To observe the electron spin-spin interaction we have to measure the electron spin precession in two spin system separately.…”