Development of tunable THz wire lasers

这项拟议的研究旨在开发可广泛调谐的太赫兹量子级联激光器(THzQCL)，该研究基于一种新的调谐机制，该机制最近(2009年)由提议的首席研究小组演示。这种调谐机制与在可调谐激光器中实现的所有其他方法本质上不同，在可调谐激光器中，通过改变波矢的介电常数或纵向分量来调谐已经制造的激光器件的频率。这种新型调谐机制利用了太赫兹频率下相对较长的波长，并且是在线激光器的极端极限下实现的，线激光器的横截面远小于波长。智能优点：线激光器的概念是新的，它是最近才通过分析这些激光器出人意料的光束模式而发展起来的。这款不同寻常的设备有许多独特的特性。其中之一是可以通过改变横模分布来调谐激光频率。更广泛的影响：首席调查员应邀在许多著名会议上作特邀/全体会议/主旨演讲。PI小组的工作也被广泛的社区媒体报道，如技术评论、激光聚焦和NPR Market Place。通过合作，PI小组开发的太赫兹激光通过增加一个关键的启动组件，帮助加强了与太赫兹相关活动的其他机构的基础设施。首席研究员将把研究项目中的元素纳入固态物理研究生课程和本科生核心课程信号与系统。

The proposed research seeks to develop broadly tunable terahertz quantum-cascade lasers (THz QCLs) based on a novel tuning mechanism that was recently (in 2009) demonstrated by the proposing principal investigator's group. This tuning mechanism is qualitatively different from all the other methods implemented in tunable lasers, in which either the dielectric constant or the longitudinal component of the wavevector is changed to tune the frequency of an already fabricated laser device. The novel tuning mechanism takes advantage of the relatively long wavelength at THz frequencies and is achieved in the extreme limit of wire lasers, whose cross section is much smaller than the wavelength. Intellectual merit: The concept of wire lasers is new, and it was developed only recently by analyzing unexpected beam patterns of these lasers. There are many unique properties associated with this unusual device. One of them is that the laser frequency can be tuned by changing the transverse mode profile. Broader impacts: The principal investigator has been invited to give invited/plenary/keynote talks at many prestigious conferences. The work from the PI's group has also been reported in media for broad communities such as Technology Review, Laser Focus, and NPR Market Place. Through collaborations, the THz lasers developed in the PI's group have helped to enhance infrastructures at other institutions in THz-related activities by adding a crucial enabling component. The principal investigator will incorporate elements in the research project into a graduate course in solid-state physics and a undergraduate core course Signals and Systems.