Optomechanical Enhancement of Doubly Resonant 2D Optical Nonlinearity

Abstract

Emerging two-dimensional semiconductor materials possess a giant second order nonlinear response due to excitonic effects while the monolayer thickness of such active materials limits their use in practical nonlinear devices. Here, we report 3300 times optomechanical enhancement of second harmonic generation from a MoS2 monolayer in a doubly resonant on-chip optical cavity. We achieve this by engineering the nonlinear light-matter interaction in a microelectro-mechanical system enabled optical frequency doubling device based on an electrostatically tunable Fabry-Perot microresonator. Our versatile optomechanical approach will pave the way for next generation efficient on-chip tunable light sources, sensors, and systems based on molecularly thin materials.

Nonlinear optics of two‐dimensional transition metal dichalcogenides

“…168 The ability of enhancing light-mater interaction motivates researchers to incorporate those optical cavies to layered TMDs. Recently, TMDs were integrated to various cavities such as the waveguides, 67 photonic crystals, [169][170][171] and plasmonic resonators [172][173][174][175] to enhance their nonlinear performance.…”

“…Yi et al fabricated a doubly resonant optical cavity with a microelectro-mechanical system, in which the distributed Bragg reflector mirror and the electrically deformed silver mirror were combined together ( Figure 7C). 170 The resonance can be engineered by tuning the Fabry-Perot cavity length so that both the excitation and SHG electric field can be enhanced simultaneously. An enhancement factor of 3300 times was achieved as shown in the spectra in Figure 7C.…”

Plasmonic Enhancement and Manipulation of Optical Nonlinearity in Monolayer Tungsten Disulfide

“…However, the nonlinear conversion efficiencies in monolayer TMDCs are still limited by their atomic thickness (<1 nm). Recently, much effort has been directed to enhance second‐harmonic (SH) emission intensity from TMDCs by utilizing optical microcavities and waveguides, but only relatively small enhancement factors (EFs) have been achieved in most of these works (≈5–10), resulting from the weak enhancement of the resonant field. A large EF has been reported from monolayer molybdenum disulfide (MoS 2 ) in a double‐resonant optomechanical cavity, but the complicated 3D cavity structure is not suitable for applications in on‐chip nonlinear optics.…”

Cavity nonlinear optics with layered materials

“…Yi et. al., solved this problem by creating a mechanically tunable Fabry-Perot cavity [12], where the bottom mirror is a DBR, and the top mirror is a capacitively actuated silver mirror (Fig. 4a).…”