Modulation of Single Photon Emission from Suspended 1L WSe under Electrostatically Induced Strain.

Tungsten diselenide (WSe) monolayers under strain are promising hosts for quantum emitters. To date, WSe quantum emitter strain engineering has focused primarily on draping WSe monolayers on patterned substrates and nanoindentation, which suffer from poor control over strain. In this work, we employ an electrostatic approach to dynamically control tensile strain in monolayer WSe suspended over micron-scale cavities with a back gate contact. Room-temperature measurement of electrostatically induced deflection and photoluminescence at = 100 K shows that a 0.22-0.26% increase in tensile strain can be achieved at modest gate voltages. Sharp localized emitters showed improvement in single photon purity from g(0) = 0.55 ± 0.04 at 0 V to g(0) = 0.40 ± 0.05 at -30 V due to strain-induced alignment of defect and dark exciton states and classical light background suppression.