Phase-coherent transport and spin relaxation in InAs nanowires grown by molecule beam epitaxy

Abstract

We report low-temperature magnetotransport studies of individual InAs nanowires grown by molecule beam epitaxy. At low magnetic fields, the magnetoconductance characteristics exhibit a crossover between weak antilocalization and weak localization by changing either the gate voltage or the temperature. The observed crossover behavior can be well described in terms of relative scales of the transport characteristic lengths extracted based on the quasi-one-dimensional theory of weak localization in the presence of spin-orbit interaction. The spin relaxation length extracted from the magnetoconductance data is found to be in the range of 80–100 nm, indicating the presence of strong spin-orbit coupling in the InAs nanowires. Moreover, the amplitude of universal conductance fluctuations in the nanowires is found to be suppressed at low temperatures due to the presence of strong spin-orbit scattering.

Measurements of spin–orbit interaction in epitaxially grown InAs nanosheets

“…The extracted 𝐿𝐿 𝑠𝑠𝑠𝑠 shows a weak dependence on 𝑉𝑉 𝑏𝑏𝑏𝑏 and is ~155 nm. This value of 𝐿𝐿 𝑠𝑠𝑠𝑠 is comparable to the values extracted in several other III-V narrow bandgap semiconductor nanostructures with a strong SOI, such as InSb nanosheets, 15 InSb nanowires, 36 and InAs nanowires, 35,40 where the values of 𝐿𝐿 𝑠𝑠𝑠𝑠 are on the order of 150-300 nm, 100-400 nm and 100-200 nm, respectively, and thus indicates the presence of a strong SOI and therefore a strong spin relaxation process in the InAs nanosheet. In the present work, the device is made from a thin WZ InAs nanosheet with {21 � 1 � 0} surface planes and the transport is most likely along the [0001] crystallographic direction.…”

“…Here, it is generally seen that the magnetoconductance shows a peak at zero field, the WAL characteristics, due to SOI in the InAs nanosheet. However, the peak-like structure in the low-field magnetoconductance is gradually weakened as 𝑉𝑉 𝑏𝑏𝑏𝑏 decreases and the magnetoconductance turns to show a broad dip structure, the weak localization (WL) characteristics, when 𝑉𝑉 𝑏𝑏𝑏𝑏 becomes less than −11 V. This gate-tunable WAL-WL crossover in the low-field magnetoconductance, which has been observed in, e.g., InAs nanowires, 35 InSb nanowires, 36 and Bi2O2Se nanoplates, 37 is a result of competing for a dominant role in low-field quantum transport between the phase coherence length and the SOI length in the InAs nanosheet.…”

Strong spin–orbit interaction and magnetotransport in semiconductor Bi2O2Se nanoplates

“…As the back gate voltage decreases towards negative values, the WAL characteristics are gradually suppressed and the magnetoconductance shows dominantly the WL characteristics. Such a gate-voltage tunable crossover between WAL and WL has also been observed in systems with strong spin-orbit interaction, such as AlxGa1-xN/GaN heterostructures 28 , InAs nanowires 29,30 and InSb nanowires 31 .…”

Weak localization and size effects in thin In 2 O 3 films prepared by autowave oxidation

“…After analyzing experimental works on the study of phase-coherence length temperature dependence in structured materials [29,30,54,[56][57][58][59][60][61],…”

“…The quantum-interference phenomena include weak localization (WL) [13,27], electron-electron interactions [28] and, if there is notable spin-orbital coupling, weak antilocalization [29]. Moreover, universal conductance fluctuations [30], Aharonov-Bohm oscillations [31] and Altshuler-AronovSpivak oscillations [32,33] can be implemented on structured materials with particular dimensions.…”