dominant contribution of the Q/Q’ valleys in the development of the SC state would be consistent with the high ($\gtrsim50$T) in-plane upper critical field, $H_{c2}^{||}$, observed in ion-gated MoS$_2$ [@LuScience2015; @SaitoNatPhys2016] and WS$_2$ [@LuPNAS2018]. The $H_{c2}^{||}$ enhancement is caused by locking of the spin of the Cooper pairs in the out-of-plane direction in a 2d superconductor in the presence of finite SOC, and is therefore promoted by increasing the SOC. However, $H_{c2}^{||}$ for MoS$_2$ and WS$_2$ is higher than in metallic TMD Ising superconductors (such as NbSe$_2$ and TaS$_2$), where $H_{c2}^{||}\lesssim30$T [@delaBarreraNatCommun2018], despite the SOC in the K/K’ valleys being much smaller ($\sim3$meV for MoS$_2$[@KormanyosPRB2013]). Spin-valley locking in the Q/Q’ valleys may thus explain this apparent inconsistency in the physics of ion-gated semiconducting TMDs under magnetic field.

From the experimental point of view, the possible multi-valley character of transport in gated TMDs is currently debated. Refs. measured the Landau-level degeneracy at moderate $n_{2d}\sim10^{12}-10^{13}$cm$^{-2}$, finding it compatible with a carrier population in the Q/Q’ valleys. However, Ref. argued that this would be suppressed for larger $n_{2d}\gtrsim10^{13}$cm$^{-2}$, typical of ion-gated devices and mandatory for the emergence of SC) due to stronger confinement within the first layer[@ChenPRL2017]. In contrast, angle-resolved photoemission spectroscopy in 