相关论文: Terahertz control of surface topology probed with …
Nanophotonic technologies offer great promise for ultra-low power optical signal processing, but relatively few nonlinear-optical phenomena have yet been explored as bases for robust digital…
In many realistic topological materials, more than one kind of fermions contribute to the electronic bands crossing the Fermi level, leading to various novel phenomena. Here, using momentum-resolved inelastic electron scattering, we…
We propose a 3D topolectrical (TE) network that can be tuned to realize various higher-order topological gapless and chiral phases. We first study a higher-order Dirac semimetal phase that exhibits a hinge-like Fermi arc linking the Dirac…
Manipulating the topological properties of insulators, encoded in invariants such as the Chern number and its generalizations, is now a major issue for realizing novel charge/spin responses in electron systems. We propose that a simple…
The Fermi surface topology of a triple non-hermitian (NH) Weyl semimetal (WSM) driven by bi-circularly polarized light is presented in this study. A NH WSM in particular has remarkable outlines. Bi-circular light, however, modifies the…
Topological systems are inherently robust to disorder and continuous perturbations, resulting in dissipation-free edge transport of electrons in quantum solids, or reflectionless guiding of photons and phonons in classical wave systems…
Novel phases of matter with unique properties that emerge from quantum and topological protection present an important thrust of modern research. Of particular interest is to engineer these phases on demand using ultrafast external stimuli,…
Crystalline phase transitions in two-dimensional materials enable precise control over electronic and ferroic properties, making them attractive materials for memory and energy storage applications. In$_2$Se$_3$ is particularly promising…
The switchable optical and electrical properties of phase change materials (PCMs) are finding new applications beyond data storage in reconfigurable photonic devices. However, high power heat pulses are needed to melt-quench the material…
We perform ultrahigh resolution angle-resolved photoemission experiments at a temperature T=0.8 K on the type-II Weyl semimetal candidate WTe$_{2}$. We find a surface Fermi arc connecting the bulk electron and hole pockets on the (001)…
The electric field induced quantum phase transition from topological to conventional insulator has been proposed as the basis of a topological field effect transistor [1-4]. In this scheme an electric field can switch 'on' the ballistic…
Directional photocurrents in two-dimensional materials arise from broken crystal symmetry, offering pathways to high-speed, bias-free photodetection beyond conventional devices. Tungsten ditelluride (WTe$_2$), a type-II Weyl semimetal,…
A recently emerging concept for quantum phase discovery is the controlled gapping of linear band crossings in topological semimetals. For example, achieving topological superconducting and charge-density-wave (CDW) gapping could introduce…
The spin-orbit coupling field, an atomic magnetic field inside a Kramer's system, or discrete symmetries can create a topological torus in the Brillouin Zone and provide protected edge or surface states, which can contain relativistic…
Stacking and twisting atom-thin sheets create superlattice structures with unique emergent properties, while tailored light fields can manipulate coherent electron transport on ultrafast timescales. The unification of these two approaches…
We experimentally demonstrate intensity and phase modulation of terahertz radiation using actively controlled large-area planar metamaterial (metafilm) hybridized with a 12 um thick layer of a liquid crystal. Active control was introduced…
Emerging photo-induced excitonic processes in transition metal dichalcogenide (TMD) heterobilayers, e.g., coupling, dephasing, and energy transfer of intra- and inter-layer excitons, allow new opportunities for ultrathin photonic devices.…
The investigation of topological state transition in carefully designed photonic lattices is of high interest for fundamental research, as well as for applied studies such as manipulating light flow in on-chip photonic systems. Here, we…
Topological photonics provides a robust and flexible platform for controlling light, enabling functionalities such as backscattering-immune edge transport and slow-light propagation. In this work, we design and characterize photonic…
Weyl semimetals are phases of matter with gapless electronic excitations that are protected by topology and symmetry. Their properties depend on the dimensions of the systems. It has been theoretically demonstrated that five-dimensional…