在TaIrTe₄中观察到大的横向热电效应
Large Transverse Thermoelectric Effect in Weyl Semimetal TaIrTe$_4$ Engineered for Photodetection
AI总结：
研究通过工程化TaIrTe₄的晶体边缘与电极的取向以及热环境，揭示了可见或远红外远场照明下异常光电流的来源是大横向热电效应，并展示了通过基板工程局部增强光电流的方法，为宽波段光电检测方案提供了新框架。
摘要：
异常局部光电流的产生通过二次非线性和热电响应是许多拓扑半导体的特征。这些光电流的出现本质上与晶体晶格的对称性破缺和各向异性密切相关。对II型韦尔半导体（WTe₂，MoTe₂，TaIrTe₄）的研究报告了异常、非局部的光电流，这些电流集中在晶体边缘或远离电极，且高度依赖于材料样品的几何形状。虽然最初归因于非线性电荷电流响应，但最近研究表明这些电流也可以归因于材料的各向异性塞贝克系数。在这里，我们确认在可见或远红外远场照明下TaIrTe₄中观察到的异常光电流来源于大横向热电效应。我们通过工程化TaIrTe₄中晶体边缘与电极的相对取向以及热环境来控制和增强其空间光电流响应。我们展示了基板工程可以局部增强光电流。这种热设备工程框架可以通过利用光电流的频谱和空间依赖性，为波前传感、光束定位和边缘检测等应用提供宽波段光电检测方案。
英文摘要：
Anomalous local photocurrent generation via second-order nonlinear and thermoelectric responses is a signature of many topological semimetals. The emergence of these photocurrents is inherently linked to symmetry breaking and anisotropy of their crystal lattices. Studies of type-II Weyl semimetals of group C$_{2v}$ (WTe$_2$, MoTe$_2$, TaIrTe$_4$) have reported anomalous, nonlocal photocurrents localized to crystals edges or far from electrodes, which are highly dependent on the geometry of the material sample. While originally attributed to a nonlinear charge current response, it was recently shown that these currents could instead be attributed to the anisotropic Seebeck coefficients of the materials. Here, we confirm that anomalous photocurrents observed in TaIrTe$_4$ under either visible or far-infrared far-field illumination originate from the large transverse thermoelectric effect. We engineer the mutual orientation of crystal edges and electrodes as well as the thermal environment of TaIrTe$_4$ to control and amplify its spatial photocurrent response. We show that substrate engineering can locally enhance photocurrent. This framework of thermal device engineering can enable broadband photo detection schemes by leveraging spectral and spatial dependence of photocurrents for applications like wavefront sensing, beam positioning, and edge detection.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
