All-optical nonreciprocity due to valley polarization pumping in transition metal dichalcogenides
Abstract
Nonreciprocity and nonreciprocal optical devices play a vital role in modern photonic technologies by enforcing one-way propagation of light. Here, we demonstrate an all-optical approach to nonreciprocity based on valley-selective response in transition metal dichalcogenides (TMDs). This approach overcomes the limitations of magnetic materials and it does not require an external magnetic field. We provide experimental evidence of photoinduced nonreciprocity in a monolayer WS2 pumped by circularly polarized (CP) light. Nonreciprocity stems from valley-selective exciton population, giving rise to nonlinear circular dichroism controlled by CP pump fields. Our experimental results reveal a significant effect even at room temperature, despite considerable intervalley-scattering, showing promising potential for practical applications in magnetic-free nonreciprocal platforms. As an example, here we propose a device scheme to realize an optical isolator based on a pass-through silicon nitride (SiN) ring resonator integrating the optically biased TMD monolayer.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 18, 2021
- Source ID
- 10.1038/s41467-021-24138-0
Entities
People
- Alexander B Khanikaev
- Andrea Alù
- Anton Vakulenko
- Filipp Komissarenko
- Kai Chen
- Sriram Guddala
- Svetlana Kiriushechkina
- Vinod Menon
- Yuma Kawaguchi
Organizations
- National Science Foundation
- Simons Foundation
- United States Department of Defense