Gate-tunable weak antilocalization in a few-layer InSe

Abstract

Indium selenide (InSe) has attracted tremendous research interest due to its high mobility and potential applications in next-generation electronics. However, the underlying transport mechanism of carriers in thin InSe at low temperatures remains unknown. Here we report the gate voltage and temperature-dependent magnetotransport properties of $\ensuremath{\gamma}$-InSe transistor devices with Hall mobility up to $2455\phantom{\rule{0.16em}{0ex}}\mathrm{c}{\mathrm{m}}^{2}\phantom{\rule{0.16em}{0ex}}{\mathrm{V}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$ at the temperature of 1.7 K. We observe a gate-tunable weak antilocalization behavior at lower magnetic field $B$, which shows a transition to weak localization at higher $B$ region. We find that the magnetotransport data agree well with the Hikami-Larkin-Nagaoka theory. The conductivity and temperature dependence of phase-coherence length reveal that the electron-electron ($e\text{\ensuremath{-}}e$) interactions are dominated dephasing mechanism for electronic transport in $\ensuremath{\gamma}$-InSe at low temperatures. The maximum phase-coherence length is found to be 320 nm at 1.7 K, larger than that of monolayer $\mathrm{Mo}{\mathrm{S}}_{2}$ and few-layer black phosphorus. These results enrich the fundamental understanding of electronic transport properties of InSe.