Extended Data Fig. 2: Reflection contrast spectra of 2s exciton at four representative vertical electric fields.
From: Correlated interlayer exciton insulator in heterostructures of monolayer WSe2 and moiré WS2/WSe2
a–d, The two-dimensional color plots of reflection contrast spectra at the E field of 80 mV nm−1 (a), 8 mV nm−1 (b), 0 mV nm−1 (c), and −8 mV nm−1 (d). The monolayer WSe2 2s exciton resonances at p/p0 = 1/3, 2/3, and 1 in a correspond to the generalized Wigner crystal and Mott insulator states. Prominent 2s exciton resonances are still observed at p/p0 = 1 in b–d, indicating a correlated insulating state when the total doping is at one hole per moiré superlattice site.
