Unveiling the Nanoelectronic Potential of HH-rGY: A Multi-scale Study of a Novel 2D Semiconductor

The search for scalable, high-performance (HP) channel materials beyond silicon continues to drive exploration of novel two-dimensional semiconductors. Here, we present a combined first-principles and multiscale transport investigation of dihydrogen-substituted rhombic graphyne (HH-rGY), a recently proposed but underexplored carbon allotrope. By integrating density functional theory, deformation potential theory, optical response calculations, and nonequilibrium Green’s function simulations, we show that HH-rGY combines a direct band gap, high anisotropic carrier mobility, strong visible–range optical absorption, and exceptional ballistic transport in double-gate MOSFET architectures. Importantly, the optical and transport anisotropies originate from the same anisotropic dispersion of frontier carbon 2 p electronic states. The highly dispersive bands along the ΓY-direction simultaneously promote low effective masses, enhanced carrier transport, and strong interband optical transitions, leading to a unified anisotropic optoelectronic response. Device-level simulations further predict ON currents, ON/OFF ratios, near-ideal subthreshold swings, femtosecond-scale intrinsic gate delays, and ultralow power-delay products exceeding the IRDS 2023 HP targets for 2028–2034, positioning HH-rGY as a promising material platform for post-CMOS nanoelectronics and optoelectronics. The favorable effective masses and strong electrostatic controllability further suggest scalability toward the sub-10 nm regime, while the pronounced optical anisotropy indicates potential for polarization-sensitive optoelectronic applications. This study provides theoretical benchmarks for future experimental and computational investigations of next-generation carbon-based electronic platforms.