3 research outputs found
Nonlinear Dispersion Relation and Out-of-Plane Second Harmonic Generation in MoSSe and WSSe Janus Monolayers
Janus transition metal dichalcogenides are an emerging class of atomically
thin materials with engineered broken mirror symmetry that gives rise to
long-lived dipolar excitons, Rashba splitting, and topologically protected
solitons. They hold great promise as a versatile nonlinear optical platform due
to their broadband harmonic generation tunability, ease of integration on
photonic structures, and nonlinearities beyond the basal crystal plane. Here,
we study second and third harmonic generation in MoSSe and WSSe Janus
monolayers. We use polarization-resolved spectroscopy to map the full
second-order susceptibility tensor of MoSSe, including its out-of-plane
components. In addition, we measure the effective third-order susceptibility,
and the second-order nonlinear dispersion close to exciton resonances for both
MoSSe and WSSe at room and cryogenic temperatures. Our work sets a bedrock for
understanding the nonlinear optical properties of Janus transition metal
dichalcogenides and probing their use in the next-generation on-chip
multifaceted photonic devices.Comment: 10 pages, 3 figures. SI: 8 pages, 5 figure