公开(公告)号：US11705639B2

公开(公告)日：2023-07-18

申请号：US16494221

申请日：2018-03-13

申请人： BROWN UNIVERSITY

发明人： Rajind Mendis ,  Masaya Nagai ,  Daniel M. Mittleman

IPC分类号： H01Q15/24 ,  G02B5/30 ,  G02B27/28

CPC分类号： H01Q15/242 ,  G02B5/3008 ,  G02B5/3058 ,  G02B27/285

摘要： An isolator based on a waveguide-based artificial dielectric medium is scalable to a range of desired terahertz frequencies, has non-reciprocal transmission and provides low insertion loss and high isolation at various tunable terahertz frequencies, far exceeding the performance of other terahertz isolators, and rivaling that of commercial optical isolators based on the Faraday effect. This approach offers a promising new route for polarization control of free-space terahertz beams in various instrumentation applications. Artificial dielectrics are man-made media that mimic properties of naturally occurring dielectric media, or even manifest properties that cannot generally occur in nature. A simple and effective strategy implements a polarizing-beam-splitter and a quarter wave plate to form a highly effective isolator. Performance of the device is believed to exceed that of any other experimentally demonstrated method for isolation of back-reflections for terahertz beams.

公开(公告)号：US11054662B2

公开(公告)日：2021-07-06

申请号：US16467780

申请日：2017-12-11

申请人： BROWN UNIVERSITY ,  OSAKA UNIVERSITY

发明人： Rajind Mendis ,  Masaya Nagai ,  Daniel M. Mittleman

IPC分类号： G02B5/30 ,  G02B27/28

摘要： A polarizing beam splitter includes thin electrically conductive metal sheets each having an edge and a thickness substantially less than the wavelength λ of a terahertz signal. The sheets are arranged in a stack or array to define wave propagation passages for energy of a terahertz beam directed at a face formed by edges of the sheets, and constitutes an artificial dielectric which operates below cutoff to allow selective transmission through the passages and/or reflection from said face, separating polarization states of the beam with defined power splitting. The artificial dielectric beam splitter can be configured to operate over a broad terahertz band. The sheets are flat, without micropatterned surface features, are robust and simple to manufacture, and form a broad band polarizing beam slitter for terahertz radiation. Complete separation of the transmitted and reflected beam is achieved below cutoff by rotating the polarization of the input beam.