THz source development for THz nonlinear optics and industrial applications

光子学的基础研究正在使太赫兹（THz）频率（~0.1-10 THz）的实际应用成为可能，这些频率具有独特的特性，推动了无损评估（NDE）的新发展;在THz频率下，大多数干燥的非金属材料是透明的，亚毫米空间分辨率是可能的，透射率对水分含量敏感，并且可以揭示内部结构。 因此，THz NDE在许多方面都是X射线的竞争技术，但没有相关的健康风险。 了解基本的THz相互作用至关重要，以便开发支持应用的适当模型。 在我的研究实验室，我们研究木材产品的应用，开发交互模型，允许同时测量木材密度，含水量和纤维结构，最终目标是行业采用该技术。 我们将通过扩展我们过去的工作来实现这一目标，重点是开发适用于廉价，连续波，亚太赫兹成像相机的新模型。 为了进一步开展太赫兹无损检测研究，将开发一种单像素相机（用于成像研究），通过消除对探测器阵列（成本高昂）或光栅扫描（无移动部件）的需求，显着降低太赫兹成像的成本。 目标是开发一个强大的平台，适用于探索从潜艇船体检测到扫描尺寸木材的广泛应用。随着电子设备将边界推向更小的尺寸，在更高的速度下使用更大的电场，了解半导体中THz场的基本相互作用变得越来越重要和相关。 在过去的十年中，~MV/cm的聚焦太赫兹场已经成为可能，这使得太赫兹非线性光学的一个新领域迅速发展。 我们正在开发一种能够在低频（<1 THz）产生强THz场的独特源，以利用载流子的大有质动力势，使我们能够有效地将载流子动力学驱动到非线性状态。 我们计划改进我们的源，并使用它来分离与半导体中的载流子相关的体非线性响应，以追求THz非线性光学。 这项研究将提高我的研究实验室的质量和能力，特别是解决（i）适用于工业应用的商业可用技术的不断变化的景观，以及（ii）对成功采用该技术所需的新兴应用进行科学研究的需要，这反过来又将依赖于我们（iii）在基础水平上仔细研究太赫兹物质相互作用。 它将推进THz技术应用的最新技术，加强创新和行业采用，并将导致适用于木材产品和光子行业的新技术，这些技术对加拿大具有重要的经济意义。

Fundamental research in photonics is enabling real-world applications at Terahertz (THz) frequencies (~0.1-10 THz), which have unique properties driving exciting new developments in non-destructive evaluation (NDE); at THz frequencies, most dry non-metallic materials are transparent, sub-mm spatial resolution is possible, transmission is sensitive to moisture content, and internal structure can be revealed. THz NDE is therefore a competitive technology to X-rays in many ways, but without the associated health risks. It is critical to understand fundamental THz interactions, so that appropriate models can be developed supporting applications. In my research lab, we study applications to wood products, developing interaction models that allow simultaneous measurements of wood density, moisture content, and fibre structure, with the ultimate goal of industry adoption of the technology. We will accomplish this through extending our past work, with an emphasis on developing new models appropriate for inexpensive, cw, sub-THz imaging cameras that are becoming available. To further THz-NDE research, a single-pixel camera will be developed (for imaging studies), significantly reducing the cost of THz imaging by removing the need for an array of detectors (cost-prohibitive) or raster scanning (no moving parts). The goal is to develop a robust platform suitable for exploring a broad range of applications from submarine hull inspection to scanning dimensional lumber.Understanding fundamental interactions of THz fields in semiconductors is becoming important and relevant as electronic devices push the boundaries to ever-smaller sizes, using larger electric fields at higher speeds. Over the past decade, ~MV/cm focused THz fields have become available, which has allowed a new field of THz nonlinear optics to develop rapidly. We are developing a unique source capable of producing strong THz fields at low frequency (<1 THz) to exploit the large ponderomotive potential for carriers, allowing us to efficiently drive carrier dynamics into nonlinear regimes. We plan to refine our source, and use it to separate the bulk nonlinear response from that related to carriers in semiconductors to pursue THz nonlinear optics. This research will improve the quality and capability of my research lab, specifically addressing (i) the changing landscape of commercially available technologies suitable for industrial applications, and (ii) the need for scientific study of emerging applications required for successful industry adoption of the technology, which in turn will rely on our (iii) careful study of THz-matter interactions at a fundamental level. It will advance the state-of-the art in applications of THz technology, enhancing innovation and industry adoption, and will lead to new technologies appropriate for the wood products and photonics industries that are economically important to Canada.