Fig. 4: Cryogenic PL measurement and single photon emission in the quantum heterostructures.
From: Confinement of excited states in two-dimensional, in-plane, quantum heterostructures
a Temperature-dependent PL spectra (90 K to 1.6 K) of the heterostructures with the 1 min growth time-MoSe2 QDs, measured using a pulsed laser excitation (500 nW, 640 nm, 1 MHz). The emission peaks from defect states, MoSe2 QDs, and WSe2 matrix are marked with yellow, red, and blue regions, respectively. b Representative cryogenic PL spectrum of the QD heterostructures with an excitation power of 100 nW at 1.6 K. c Second-order photon correlation curve for the PL signal of the MoSe2 QDs. d TRPL spectrum for the sharp emission of the MoSe2 QDs (1.688 eV), shown in (b). The time-resolved PL data (blue line) are convoluted (black line) with the instrument response function, using an exponential function I = A*exp(−t/τ). TRPL spectrum for the defect states (1.60 eV) was added to Supplementary Fig. S17.
