Applying TERS Toward the Development of Strain-Tunable Single-Photon Sources

The native length scales of most optical and optoelectronic processes within low-dimensional quantum materials and next-generation devices are well below the diffraction limit of light. As a result, nano-optical imaging and spectroscopy techniques with resolutions in the <10- to 100-nm regime have recently been employed to characterize these technologically promising structures with great success. Here, James Schuck highlights efforts using tip-enhanced Raman scattering (TERS) and nanophotoluminescence studies to visualize the relationship between strain and quantum emitters in 2D semiconductors. These emitters are associated with localized strain that can be deterministically applied to create designer nanoarrays of single-photon sources. However, the local interplay between strain, defects, and crystal structure is unclear, and the origin of the emitter states remains unknown. Schuck discusses how he and colleagues combine room-temperature nano-optical imaging of excitons in low-defect-density WSe₂ nanowrinkles and nanobubbles with TERS-informed strained modeling to elucidate how strain-induced confinement — without crystalline defects — can create quantum-dot-like states. Results are paving the way for the realization of strain-tunable room-temperature single-photon sources in high-quality 2D semiconductors.

***This presentation premiered during the 2021 Photonics Spectra Conference Spectroscopy track. For information on upcoming Photonics Media events, see our event calendar here.

About the presenter
P. James Schuck, Ph.D., is Associate Professor of mechanical engineering at Columbia University. He specializes in the study of sensing and engineering phenomena emerging from nanostructures and interfaces, with a focus on developing and applying advanced nano-optical probes and plasmonic devices. His approaches are typically grounded in (nano) optical, scan-probe, and single-molecule imaging techniques, which provide unique access to behavior at relevant length and time scales in real environments encountered in energy and biological applications. With his research he aims to characterize, understand, and control light-matter interactions at the level of single photons and electrons. Schuck was a postdoctoral student at Stanford University and a senior scientist at Lawrence Berkeley National Laboratory. He received his PhD in 2003 from Yale University and his BA in 1997 from UC Berkeley.