Soyeong Kwon1,Jin Myung Kim1,Peiwen J. Ma1,Weilin Guan1,SungWoo Nam1
University of California, Irvine1
Soyeong Kwon1,Jin Myung Kim1,Peiwen J. Ma1,Weilin Guan1,SungWoo Nam1
University of California, Irvine1
Recent discoveries on atomically thin Van der Waals materials have suggested new strategies for optoelectronic devices with reduced dimensionality and high elastic modulus. In particular, transition metal dichalcogenides (TMDs) and their vertical heterostructures host in-plane and out-of-plane interlayer excitons which can be tailored through strain engineering. In this talk, we investigated the interface phenomena in uniaxially strained TMD heterostructure. We prepared MoSe<sub>2</sub>/WSe<sub>2</sub> heterostructure on an elastomeric substrate with near zero twist angle and performed photoluminescence and reflectance measurements. We found the signature of interlayer excitons and compared their behaviors in unstrained and strained regions in far-field optical characterizations. Furthermore, near-field mapping and spectroscopic methods of photo-induced force microscopy enabled nanoscale analysis of interlayer exciton coupling controllable with the strain magnitude. These results suggest that strain-modulated electronic and optical properties of twisted TMD/TMD heterostructures will be utilized for modifying interlayer exciton trapping and diffusion behaviors.