Fig. 1: Steady-state and transient correlated state detection via exciton sensing.
From: Time-domain signatures of distinct correlated insulators in a moiré superlattice
a Schematic of device architecture where the WSe2/WS2 heterobilayer is symmetrically encapsulated by top and bottom gates (Vt and Vb, respectively) consisting of hexagonal boron nitride (h-BN) and few-layer graphene (Gr). b Gated (Vg = Vt = Vb) steady-state reflectance spectrum of the lowest energy moiré exciton of WSe2. Here, Δ R = R – R0 where R is the reflected signal from the bilayer and dual gate region while R0 is the reflected signal from a region with gates and no bilayer. c–e Gated (Vg = Vt = Vb) transient reflectance response as a function of pump fluence at Δt = 2, 8, 50 ps, respectively. Shown is the integrated response centralized around the lowest energy WSe2 moiré exciton sensor. The different fluence-dependent responses have been offset and multiplied by −1 for clarity. Associated fluence labels are shown on the side of panel e and are consistently colored throughout the other panels. Here, ΔR = Ron – Roff where the subscript indicates either pump-on or -off spectra. See Methods for further details. All data were collected at 11 K.
