Subband dependent g-factor in a monolayer WSe₂ 1D channel

One of the most promising and exciting family of two-dimensional (2D) materials is the semiconducting transition metal dichalcogenides (TMDs). Their lack of inversion symmetry at the monolayer limit and the presence of transition metals leads to opposite spins being locked to opposite valleys, also known as spin-valley locking, a phenomenon that can be leveraged for many quantum technologies. The difficulty in achieving low resistance ohmic contacts and having high quality materials make quantum transport measurements in monolayer TMDs challenging. In this presentation, we demonstrate ballistic transport in low contact resistance and high mobility samples (> 20,000 cm²V^-1s^-1) with gate defined 1D channels and nano-constrictions in monolayer tungsten diselenide (WSe₂). We observe well defined conductance quantization up to G = 8 e²/h, and demonstrate that the hole effective g-factor in this system depends on the total amount of populated 1D subbands.