相关论文: Measuring valley polarization in two-dimensional m…

We demonstrate a simple and scalable approach to increase conversion efficiencies of nonlinear metasurfaces by incorporating them into multipass cells and by letting the pump beam to interact with the metasurfaces multiple times. We…

High-harmonic spectroscopy driven by circularly-polarized laser pulses and their counter-rotating second harmonic is a new branch of attosecond science which currently lacks quantitative interpretations. We extend this technique to the…

Valleytronics aims to control electrons in a valley-specific manner for quantum information manipulation. Due to their strong in-plane anisotropy, which enables polarization-controlled optical transitions to distinct nondegenerate valleys,…

Second-harmonic generation (SHG) is a well-known nonlinear spectroscopy method to probe electronic structure, specifically, in transition metal dichalcogenide (TMDC) monolayers. This work investigates the nonlinear dynamics of a strongly…

We propose a practical scheme to generate a pure valley current in monolayer transition metal dichalcogenides by one-photon absorption of linearly polarized light. We show that the pure valley current can be detected by either…

We study the higher-harmonic generation (HHG) using elliptically polarized two-color driving fields. The HHG via bi-chromatic counter-rotating laser fields is a promising source of circularly polarized ultrashort XUV radiation at the…

Polarization plays an important role in various time-domain astrophysics to understand the magnetic fields, geometry, and environments of spatially unresolved variable sources. In this paper we present the results of laboratory and on-sky…

Manipulating the valley degree of freedom to encode information for potential valleytronic devices has ignited a new direction in solid-state physics. A significant, fundamental challenge in the field of valleytronics is how to generate and…

The signal demixing problem seeks to separate a superposition of multiple signals into its constituent components. This paper studies a two-stage approach that first decompresses and subsequently deconvolves the noisy and undersampled…

We recently shown, using tight-binding calculations, that nonequilibrium valley polarization can be realized in graphene, when the current is injected through "valley filter": a ballistic point contact with zigzag edges. Here we…

Accurately measuring the geometry and spatially-varying reflectance of real-world objects is a complex task due to their intricate shapes formed by concave features, hollow engravings and diverse surfaces, resulting in inter-reflection and…

Second-harmonic emission at a frequency that is twice the laser frequency is an important diagnostic for nonlinear laser-plasma interaction. It is forbidden for centrosymmetric materials such as the bulk of sapphire. The symmetry, however,…

The BiTeX family of polar van der Waals (vdW) semiconductors offers a unique platform for exploring the interplay between polar crystalline structure and nonlinear optical phenomena. Here, we utilize second harmonic generation (SHG)…

The objective of polarization rendering is to simulate the interaction of light with materials exhibiting polarization-dependent behavior. However, integrating polarization into rendering is challenging and increases computational costs…

We measured the lifetime of optically created valley polarization in single layer WS2 using transient absorption spectroscopy. The electron valley relaxation is very short (< 1ps). However the hole valley lifetime is at least two orders of…

Monolayers of transition metal dichacogenides show strong second-order nonlinearity and symmetry-driven selection rules from their three-fold lattice symmetry. This process resembles the valley-contrasting selection rules for…

The concept of ferrovalley materials has been proposed very recently. The existence of spontaneous valley polarization, resulting from ferromagnetism, in such hexagonal two-dimensional materials makes nonvolatile valleytronic applications…

Since de discovery of graphene, the family of 2-dimensional materials has attracted much recent attention. In this work, the nonlinear optical properties of few-layer MoS2 two-dimensional crystals are studied using femtosecond laser pulses.…

The band structure of transition metal dichalcogenides (TMDCs) with valence band edges at different locations in the momentum space could be harnessed to build devices that operate relying on the valley degree of freedom. To realize such…

We utilize few-level model systems to analyze the polarization and phase properties of below-threshold harmonics generated from aligned molecules. In a two-level system, we find that the phase of emitted harmonics undergoes a distinct…