相关论文: Electric-field switchable second-harmonic generati…
We experimentally study nonlinear generation of the second harmonic by backward volume spin waves propagating in microscopic magnonic waveguides fabricated from a low-loss magnetic insulator with a thickness of several tens of nanometers.…
Bilayer (2L) transition metal dichalcogenides (TMD) have the ability to host interlayer excitons, where electron and hole parts are spatially separated that leads to much longer lifetime as compared to direct excitons. This property can be…
Layered two-dimensional (2D) materials, with their atomic-scale thickness and tunable electronic, optical, and mechanical properties, open many promising pathways to significantly advance modern electronics. The field effect caused by a…
Valley-contrasting Hall transport conventionally relies on the inversion symmetry breaking in two-dimensional systems, which greatly limits the selection range of valley materials. In particular, while monolayer transition metal…
We present a theoretical study of second-harmonic generation from a singular metasurface. The singular metasurfaces strongly interact with the incident light, where the large field enhancement forms an intense surface polarization that…
3R-MoS2, a MoS2 polytype with broken inversion symmetry, enables unique light-matter interactions and is promising for linear and nonlinear integrated photonics beyond the monolayer limit. Yet, systematic studies of its thickness-dependent…
First-principles calculations, within the framework of density functional theory, have been performed on the well-studied 2H and the less explored 1T$^{\prime}$ phase of single-layer MoS$_{2}$. We have addressed the strain-induced…
Second-order nonlinearity gives rise to many distinctive physical phenomena, e.g., second-harmonic generation, which plays an important role in fundamental science and various applications. Lithium niobate, one of the most widely used…
Efficient frequency conversion techniques are crucial to the development of plasmonic metasurfaces for information processing and signal modulation. In principle, nanoscale electric-field confinement in nonlinear materials enables higher…
Topological magnons, quantized spin waves featuring nontrivial boundary modes, present a promising route toward lossless information processing. Realizing practical devices typically requires magnons excited in a controlled manner to enable…
The 4-bar crystal symmetry in materials such as GaAs can enable quasi-phasematching for efficient frequency conversion without poling, twinning or other engineered domain inversions. 4-bar symmetry means that a 90 degree rotation is…
Efficient nonlinear wave mixing is of paramount importance for a wide range of applications. However, weak optical nonlinearities pose significant challenges for accessing nonlinear light-matter interaction in compact systems. Here, we…
Lithium niobate (LN) metasurfaces exhibit remarkable Pockels effect-driven electro-optic tunability, enabling dynamic control of optical responses through external electric fields. When combined with their high second-order nonlinear…
Little is known about the role of weak interlayer coupling in the second harmonic generation (SHG) effects of two-dimensional van der Waals (vdW) systems. In this article, taking homo-bilayer $MoS_2/MoS_2$ and hetero-bilayer $MoS_2/MoSe_2$…
The ability to engineer metamaterials with tunable nonlinear optical properties is crucial for nonlinear optics. Traditionally, metals have been employed to enhance nonlinear optical interactions through field localization. Here, inspired…
Strong magnetic fields profoundly affect the quantum physics of charged particles, as seen for example by the integer and fractionally quantized Hall effects, and the fractal `Hofstadter butterfly' spectrum of electrons in the presence of a…
We investigate the generation of ultraviolet (UV) second-harmonic radiation on the boundary of a UV transparent crystal, which is derived from the automatic partial phase matching of the incident wave and the total internal reflection. By…
We report the observation of second harmonic generation with high conversion efficiency $\sim 0.005\%$ in the terahertz regime from thin films of the topological insulator Bi$_2$Se$_3$ that exhibit the linear photogalvanic effect, measured…
Twisted graphene bilayers provide a versatile platform to engineer metamaterials with novel emergent properties by exploiting the resulting geometric moir\'{e} superlattice. Such superlattices are known to host bulk valley currents at tiny…
Two-dimensional transition metal dichalcogenides (TMDC) have shown promise for various applications in optoelectronics and so-called valleytronics. Their operation and performance strongly depend on the stacking of individual layers. Here,…