相关论文: Size-effects on shift-current in layered CuInP$_2$…
We investigate the effect of local electron-phonon coupling on nonlinear optical conductivity in an interacting ferroelectric system. Using real-time simulations, we show an enhancement in nonlinear conductivity under linearly-polarized…
We use a first-principles density functional theory approach to calculate the shift current and linear absorption of uniformly illuminated single-layer Ge and Sn monochalcogenides. We predict strong absorption in the visible spectrum and a…
2D ferroelectric (FE) materials have opened new opportunities in non-volatile memories, computation and non-linear optics due to their robust polarization in the ultra-thin limit and inherent flexibility in device integration. Recently,…
We elucidate light-induced orbital and spin current through nonlinear response theory, which generalizes the well-known bulk photovoltaic effect in centrosymmetric broken materials from charge to the spin and orbital degrees of freedom. We…
The discovery of two-dimensional (2D) materials possessing switchable spontaneous polarization with atomic thickness opens up exciting opportunities to realize ultrathin, high-density electronic devices with potential applications ranging…
Semiconducting 2D materials, such as molybdenum disulfide (MoS2) and other members of the transition metal dichalcogenide family, have emerged as promising materials for applications in high performance nanoelectronics that exhibit…
Ferroelectric metals, characterized by the coexistence of ferroelectricity and metallic conductivity, present a fundamental challenge due to the screening effect of free charge carriers on the long-range electric dipole order. Existing…
The in-plane photoelectric (IPPE) effect is a recently discovered [Sci. Adv. \textbf{8}, eabi8398 (2022)] quantum phenomenon which enables efficient detection of terahertz (THz) radiation in semiconductor structures with a two-dimensional…
Photocurrents in nanotube p-n junctions are calculated using a non-equilibrium Green function quantum transport formalism. The short-circuit photocurrent displays band-to-band transitions and photon-assisted tunneling, and has multiple…
We investigate the shift current bulk photovoltaic response of materials close to a band inversion topological phase transition. We find that the bulk photocurrent reverses direction across the band inversion transition, and that its…
Two-dimensional (2D) transition metal dichalcogenides like molybdenum diselenide (MoSe$_2$) have shown great potential in optoelectronics and energy storage due to their layer-dependent bandgap. However, producing high-quality 2D MoSe$_2$…
Realization of giant and continuously tunable second-order photocurrent is desired for many nonlinear optical (NLO) and optoelectronic applications, which remains to be a great challenge. Here, based on a simple two-band model, we propose a…
The bulk photovoltaic effect (BPVE) refers to current generation due to illumination by light in a homogeneous bulk material lacking inversion symmetry. In addition to the intensively studied shift current, the ballistic current, which…
The bulk photovoltaic effect provides a fundamental pathway for direct light-to-current conversion in quantum materials. However, these nonlinear currents are often strictly constrained or forbidden by crystal symmetries, hindering their…
Ferroelectric field-effect transistors (FeFET) with two-dimensional (2D) semiconductor channels are promising low-power, embedded non-volatile memory (NVM) candidates for next-generation in-memory computing. However, the performance of…
Quasi-two-dimensional (quasi-2D) metal halide perovskites exhibit rich phase heterogeneity that profoundly influences light-matter interactions and charge transport. However, the fundamental mechanisms governing carrier transfer across…
The pursuit for "ferroelectric metal" which combines seemingly incompatible spontaneous electric polarization and metallicity, has been assiduously ongoing but remains elusive. Unlike traditional ferroelectrics with a wide band gap,…
Tungsten diselenide (WSe2), a semiconducting transition metal dichalcogenide (TMDC), shows great potential as active material in optoelectronic devices due to its ambipolarity and direct bandgap in its single-layer form. Recently, different…
We investigate the optoelectronic properties of single indium arsenide nanowires, which are grown vertically on p-doped silicon substrates. We apply a scanning photocurrent microscopy to study the optoelectronic properties of the single…
Photostriction is predicted for SnS and SnSe monolayers, two-dimensional ferroelectrics with rectangular unit cells (the lattice vector $\mathbf{a}_1$ is larger than $\mathbf{a}_2$) and an intrinsic dipole moment parallel to $\mathbf{a}_1$.…