Daghero
- Srinivasa Reddy Tamalampudi
- Duhee Yoon
- 'Andrea C. Ferrari'
- 'Renato S. Gonnelli'
title: 'Multi-Valley Superconductivity In Ion-Gated MoS$_2$ Layers'
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Transition metal dichalcogenides (TMDs) are layered materials with a range of electronic properties. Depending on chemical composition, crystalline structure, number of layers (N), doping, and strain, different TMDs can be semiconducting, metallic and superconducting[@FerrN2015]. Amongst semiconducting TMDs, MoS$_2$, MoSe$_2$, WS$_2$ and WSe$_2$ have sizeable bandgaps in the range$\sim$1-2eV[@WangNN2012]. When exfoliated from bulk to single layer (1L), they undergo an indirect-to-direct gap transition[@MakPRL2010; @SpleNL2010; @WangNN2012], offering a platform for electronic and optoelectronic applications[@FerrN2015; @WangNN2012; @MakNP2016], such as transistors[@PodzAPL2004; @RadiNN2011; @FangNL2012], photodetectors[@GourSEMSC1997; @LeeNL2012; @YinACS2012; @KoppNN2014], modulators[@SunNP2016] and electroluminescent devices[@CarlPRB2002; @SundNL2013].

For all TMDs with 2H crystal structure, the hexagonal Brillouin Zone (BZ) features high-symmetry points $\Gamma$, M, K and K’[@SpleNL2010; @BrummePRB2015], Fig.\[figure:bands\]a. The minima of the conduction band fall at K, K’, as well as at Q, Q’, approximately half-way along the $\Gamma$-K(K’) directions[@SpleNL2010; @BrummePRB2015], Fig.\[figure:bands\]a. In absence of an out-of-plane electric field, the relative position of Q and Q’ depends on N and strain[@SpleNL2010; @LambrechtPRB2012; @BrummePRB2015]. The global minimum of the conduction band sits at K/K’ in 1L-MoS$_2$ and at Q/Q’ in few layer (FL)-MoS$_2$ 