Microsphere-coupled light emission control of van der Waals heterostructures.

Two-dimensional transition metal dichalcogenides (TMDCs) integrated into photonic structures provide an intriguing playground for the development of novel optoelectronic devices with improved performance. Here, we show the enhanced light emission from TMDC based van der Waals heterostructures through coupling with microsphere cavities. We observe cavity-induced emission enhancement of TMDC materials which varies by an order of magnitude, depending on the size of the microsphere and thickness of the supporting oxide substrate. Furthermore, we demonstrate microsphere cavity-enhanced electroluminescence of a van der Waals light emitting transistor, showing the potential of 2D material based hybrid optoelectronic structures.