Gate-tunable weak antilocalization in a few-layer InSe

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 gamma-InSe transistor devices with Hall mobility up to 2455 cm(2) V-1 s(-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-e) interactions are dominated dephasing mechanism for electronic transport in 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 MoS2 and few-layer black phosphorus. These results enrich the fundamental understanding of electronic transport properties of InSe.