Heterogeneous integrated phase modulator based on two-dimensional layered materials

Abstract

Silicon nitride, with ultralow propagation loss and a wide transparency window, offers an exciting platform to explore integrated photonic devices for various emerging applications. It is appealing to combine the intrinsic optical properties of two-dimensional layered materials with high-quality optical waveguides and resonators to achieve functional devices in a single chip. Here we demonstrate a micro-ring resonator-based phase modulator integrated with few-layer MoS 2 . The ionic liquid is employed directly on the surface of MoS 2 to form a capacitor configuration. The effective index of the composite MoS 2 – SiN waveguide can be modulated via adjusting bias voltages to achieve different charged doping induced electro-refractive responses in MoS 2 film. The maximum effective index modulation of the composite MoS 2 – SiN waveguide can be achieved to 0.45 × 10 − 3 . The phase tuning efficiency is measured to be 29.42 pm/V, corresponding to a V π L of 0.69 V·cm. Since the micro-ring resonator is designed near the critical coupling regime, the coupling condition between the bus waveguide and micro-ring resonator can also be engineered from under-coupling to over-coupling regime during the charged doping process. That can be involved as a degree of freedom for the coupling tailoring. The ability to modulate the effective index with two-dimensional materials and the robust nature of the heterostructure integrated phase modulator could be useful for engineering reliable ultra-compact and low-power-consumption integrated photonic devices.

Refractive index in ionic liquids: beyond the D line

“…Authors in Ref. [49] proposed a similar structure that also allowed the size of the two chambers to be varied by injecting or withdrawing liquid, simplifying the zoom function and minimizing aberrations.…”

“…In Ref. [49], it is proposed the fabrication of a ring microresonator consisting of a MoS layer structure on a SiN substrate coated by the IL [DEME][NTf 2 ] to control the charge doping processes. Direct and inverse bias voltages change the effective index of the waveguide, producing a change in the transmission spectra due to a redshift or a blueshift of the resonance wavelength.…”

Nonlinear Optical Response Modulated by Lattice Reconstruction in Small‐Angle Twisted Bilayer MoS2

“…[1] Beyond conventional techniques, including DOI: 10.1002/adom.202302407 doping, [2] chemical modification, [3] and electrostatic control, [4] augmenting material performance, an innovative avenue, arises through the manipulation of the relative layer twist, introducing a critical new dimension for the design of stacked structures endowed with emergent functionalities. [5,6] The variation in the twist angle between the layers serves to finely modulate not only the energyband architecture but also the overall symmetry of the system. This dual influence is of paramount importance in a wide range of physical processes, including linear optical phenomena such as photoluminescence (PL), [7,8] Raman [9,10] and nonlinear optical behaviors, including nonlinear absorption, [11] and second-harmonic generation (SHG).…”