Low-loss composite photonic platform based on 2D semiconductor monolayers

Abstract

Two dimensional materials such as graphene and transition metal dichalcogenides (TMDs) are promising for optical modulation, detection, and light emission since their material properties can be tuned on-demand via electrostatic doping. The optical properties of TMDs have been shown to change drastically with doping in the wavelength range near the excitonic resonances. However, little is known about the effect of doping on the optical properties of TMDs away from these resonances, where the material is transparent and therefore could be leveraged in photonic circuits. Here, we probe the electro-optic response of monolayer TMDs at near infrared (NIR) wavelengths (i.e. deep in the transparency regime), by integrating them on silicon nitride (SiN) photonic structures to induce strong light$-$matter interaction with the monolayer. We dope the monolayer to carrier densities of ($7.2\pm 0.8$) $\times$ $10^{13}{\text{cm}}^{-2}$, by electrically gating the TMD using an ionic liquid. We show strong electro-refractive response in monolayer tungsten disulphide (WS${}_2$) at NIR wavelengths by measuring a large change in the real part of refractive index $\Delta$n = $0.53$, with only a minimal change in the imaginary part $\Delta$k = $0.004$. The doping induced phase change ($\Delta$n), compared to the induced absorption ($\Delta$k) measured for WS${}_2$ ($\Delta$n/$\Delta$k $\sim 125$), a key metric for photonics, is an order of magnitude higher than the $\Delta$n/$\Delta$k for bulk materials like silicon ($\Delta$n/$\Delta$k $\sim 10$), making it ideal for various photonic applications. We further utilize this strong tunable effect to demonstrate an electrostatically gated SiN-WS${}_2$ phase modulator using a WS${}_2$-HfO${}_2$ (Hafnia)-ITO (Indium Tin Oxide) capacitive configuration, that achieves a phase modulation efficiency (V${}_{\pi }$L) of 0.8 V $\cdot$ cm with a RC limited bandwidth of 0.3 GHz.

References in corpus (23)

• Graphene Photonics and Optoelectronics
• Deep Learning with Coherent Nanophotonic Circuits
• Two-Dimensional Material Nanophotonics
• Observation of tightly bound trions in monolayer MoS2
• Emerging Device Applications for Semiconducting Two-Dimensional Transition Metal Dichalcogenides
• Excitons in atomically thin transition metal dichalcogenides
• Electrically Tunable Excitonic Light Emitting Diodes based on Monolayer WSe2 p-n Junctions
• Electrical Control of Two-Dimensional Neutral and Charged Excitons in a Monolayer Semiconductor
• Measurement of the optical dielectric function of transition metal dichalcogenide monolayers: MoS2, MoSe2, WS2 and WSe2
• Computational 2D Materials Database: Electronic Structure of Transition-Metal Dichalcogenides and Oxides
• Nanophotonic Lithium Niobate Electro-optic Modulators
• Quantitative Determination of the Band-Gap of WS2 with Ambipolar Ionic Liquid-Gated Transistors
• Intrinsic Transport Properties of Electrons and Holes in Monolayer Transition Metal Dichalcogenides
• Efficient, Compact and Low Loss Thermo-Optic Phase Shifter in Silicon
• Graphene-Based Integrated Photonics For Next-Generation Datacom And Telecom
• Graphene Phase Modulator
• Electric Field-Induced Second Order Nonlinear Optical Effects in Silicon Waveguides
• Effective electro-optical modulation with high extinction ratio by a graphene-silicon microring resonator
• High-modulation-efficiency InGaAsP/Si hybrid MOS optical modulator with Mach-Zehnder interferometer
• Ultra-High Electro-Optic Activity Demonstrated in a Silicon-Organic Hybrid (SOH) Modulator
• Two-dimensional metal-chalcogenide films in tunable optical microcavities
• Giant Gating Tunability of Optical Refractive Index in Transition Metal Dichalcogenide Monolayers
• Electrical 2π phase control of infrared light in a 350nm footprint using graphene plasmons

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• Integrated photonics incorporating 2D materials for practical applications
• Spatiotemporal imaging of nonlinear optics in van der Waals waveguides
• Impact of substrates and quantum effects on exciton line shapes of 2D semiconductors at room temperature
• Approaching the absorption limit with monolayer semiconductor superlattices
• Photonics in Flatland: Challenges and Opportunities for Nanophotonics with 2D Semiconductors
• Effect of electron-irradiation on layered quantum materials
• Boosting the SiN nonlinear photonic platform with transition metal dichalcogenide monolayers