Fig. 3: Schematic diagrams of irreducible Brillouin zone and split of degeneracy at the KK′ valleys of WSe2.
From: Enhanced valley splitting of WSe2 in twisted van der Waals WSe2/CrI3 heterostructures
a Irreducible Brillouin zone of WSe2. b Split of degeneracy at the KK′ valleys. In (b), σ+ and σ−denote the right-hand and left-hand circularly polarized light under optical selection rules at the KK′ valleys. The dashed lines denote the B = 0 bands. Red and blue arrows denote spin up and spin down states, respectively. CB1 (CB2) and VB1 (VB2) denote the first (second) conduction and valence bands at the K valley, while CB1′ (CB2′) and VB1′ (VB2′) denote the corresponding bands at the K′ valley. ∆CB and ∆VB are the energy shifts of the conduction and valence band, respectively.
