Experimental study of weak antilocalization effects in a high-mobilityInxGa1−xA

Abstract

The magnetoresistance associated with quantum interference corrections in a high mobility, gated InGaAs/InP quantum well structure is studied as a function of temperature, gate voltage, and angle of the tilted magnetic field. Particular attention is paid to the experimental extraction of phasebreaking and spin-orbit scattering times when weak anti-localization effects are prominent. Compared with metals and low mobility semiconductors the characteristic magnetic field Btr =h/4eDτ in high mobility samples is very small and the experimental dependencies of the interference effects extend to fields several hundreds of times larger. Fitting experimental results under these conditions therefore requires theories valid for arbitrary magnetic field. It was found, however, that such a theory was unable to fit the experimental data without introducing an extra, empirical, scale factor of about 2. Measurements in tilted magnetic fields and as a function of temperature established that both the weak localization and the weak anti-localization effects have the same, orbital origin. Fits to the data confirmed that the width of the low field feature, whether a weak localization or a weak anti-localization peak, is determined by the phase-breaking time and also established that the universal (negative) magnetoresistance observed in the high field limit is associated with a temperature independent spin-orbit scattering time. * sergei.studenikin@nrc.ca

Antilocalization and spin-orbit coupling in the hole gas in strainedGaAs∕InxGa1−xAsMinkov1, Шерстобитов2, Германенко3 et al. 2005Phys. Rev. B41081View full textAdd to dashboardCite

“…6,7,8,9 The measurements of interference induced low-filed magnetoresistance are the powerful tool for studies of the spin-splitting, spin-and phase-relaxation mechanisms. At present, there are numerous studies of n-type 2D systems 2,10,11,12,13,14,15,16 , whereas the more complicated p-type systems are studied noticeable less 17,18,19,20,21 (for more references see review article by Zawadzki and Pfeffer 22 ). As for the strained quantum well, the antilocalization and spin relaxation in 2D hole gas are practically not investigated in these systems.…”

Spin Hall and spin-diagonal conductivity in the presence of Rashba and Dresselhaus spin-orbit coupling

“…Recent observations of a spin-galvaic effect [18,24] and a spin-orbit coupling weak localization studies in these systems [17,25,26] illustrate the potential importance of these tunable interactions in semiconductor spintronics [27]. Indeed, this intricate interplay has generated several theoretical studies of their transport properties due to the anisotropies created in the Fermi surfaces for α = β [20,28] and a new proposed spin-FET [19] in the regime where λ = β motivated by the original proposal by Datta and Das [29].…”

Suppression of the parasitic buffer layer conductance in InSb/AlxIn1−xSb heterostructures using a wide-band-gap barrier layer

“…In metallic and semiconductor systems, inelastic electron-electron interactions are the dominant source of dephasing at low temperatures. 31,[38][39][40] In 2D systems, τ φ ∝ T −1 and is well described by the Nyquist dephasing rate, given by τ This analysis results in a substantial increase in μ QW , whereas the modification to the δ-layer parameters is negligible due to their comparatively small contribution to ρ 0 (and ρ 0 ). With some degree of confidence, we can therefore conclude that the low-temperature mobility of SBL-1 is greater than in MBL-1.…”