Microwave-Induced Magneto-Intersubband Scattering in a Square Lattice of Antidots

Abstract

The effect of microwave radiation on low-temperature electron magnetotransport in a square antidot lattice with a period of d ≈ 0.8 μm based on a GaAs quantum well with two occupied energy subbands E1 and E2 is investigated. It is shown that, owing to a significant difference between the electron densities in the subbands, commensurability oscillations of the resistance in the investigated antidot lattice are observed only for the first subband. It is found that microwave irradiation under the cyclotron resonance condition results in the formation of resistance oscillations periodic in the inverse magnetic field in the region of the main commensurability peak. It is established that the period of these oscillations corresponds to the period of magneto-intersubband oscillations. The observed effect is explained by the increase in the rate of intersubband scattering caused by the difference between the electron heating in the subbands E1 and E2.

Dependences of the Transport Scattering Time and Quantum Lifetime on the Two-Dimensional Electron Gas Density in Modulation-Doped Single GaAs Quantum Wells with AlAs/GaAs Short-Period Superlattice Barriers

“…However, the presence of background impurities in the single GaAs QW with AlAs/GaAs SPSL barriers hardly reduces the time τq in a 2D electron gas with a high density ne, which is due to the reduction of the random scattering potential of remote donors by X-valley electrons. For this reason, despite the moderate mobility, modulation-doped single QWs with SPSL barriers are widely used to study fundamental quantum phenomena in high-density 2D electron systems, including those with several occupied energy subbands [19][20][21][22].…”

Dynamic and static properties of stadium-shaped antidot arrays

“…On the other hand, the dynamic properties of magnetic antidot arrays are also an important issue when having in mind these systems for future applications. It is crucial to notice that the term dynamic encodes two temporal scales according to the amplitude of spin motion: while large amplitudes are related to magnetization reversal processes by means of a constant magnetic field, small amplitudes are typically encountered in ferromagnetic resonance (FMR) experiments, which ultimately refer to the excitation and propagation of spin waves [39][40][41] . This technique probes the magnetization dynamics of the samples using microwave fields whose maximum absorption occurs when the microwave frequency matches the frequency of the resonance modes of the system 42 .…”