biostudies-literatureGuo SMinistry of Education - Singapore (MOE)A*STAR | Singapore Institute of Manufacturing Technology (Singapore Institute of Manufacturing Technology - A STAR)42https://www.ebi.ac.uk/biostudies/studies/S-EPMC12764534biostudies-literatureUnknown15(1)Optical phase modulators are critical components in integrated photonics, but conventional designs suffer from a trade-off between modulation efficiency and optical loss. Two-dimensional materials like graphene offer strong electro-optic effects, yet their high optical absorption at telecom wavelengths leads to significant insertion losses. Although monolayer transition metal dichalcogenides (TMDs) provide exceptional telecom-band transparency for low-loss electro-refractive response, their practical implementation in phase modulators requires top electrodes to enable vertical electric field tuning, which typically introduces parasitic absorption. Here, we address this challenge by developing hybrid tungsten oxyselenide/graphene (TOS/Gr) electrodes that minimize optical loss while enablingLight, science & applicationsHybrid tungsten oxyselenide/graphene electrodes for near-lossless 2D semiconductor phase modulators.PMC12764534RT2/23, RG63/23M23M6c0109MOE-MOET32023-0003Choi MSLim SYu RSeung HWu QSia JXBGuo SAng LKGong XLiang CChae SHSingh LWatanabe KLeong JHuo JLee SGRanno LTaniguchi TChang WYang YHe YHu JTay BKJuperi ASBRhodes DfalseHybrid tungsten oxyselenide/graphene electrodes for near-lossless 2D semiconductor phase modulators.Optical phase modulators are critical components in integrated photonics, but conventional designs suffer from a trade-off between modulation efficiency and optical loss. Two-dimensional materials like graphene offer strong electro-optic effects, yet their high optical absorption at telecom wavelengths leads to significant insertion losses. Although monolayer transition metal dichalcogenides (TMDs) provide exceptional telecom-band transparency for low-loss electro-refractive response, their practical implementation in phase modulators requires top electrodes to enable vertical electric field tuning, which typically introduces parasitic absorption. Here, we address this challenge by developing hybrid tungsten oxyselenide/graphene (TOS/Gr) electrodes that minimize optical loss while enabling2026-01-01T00:00:00Z2026 Jan2026-06-06T10:23:51.244Z2026-05-28T03:13:24.085ZS-EPMC127645344148407010.1038/s41377-025-02058-8