Nonreciprocal Photonics for Suppression of Disorder Induced Scattering

Abstract

Isolators and circulators are frequently used in photonic systems to introduce directionality and to block the back-propagation of light. However, these non-reciprocal devices are only a fix for backscattering and do not perform any preventative function. Such fixes do nothing to address the problem of scattering from defects, which results in signal decoherence, loss of power, localized resonances, and spurious scattering. In this project we sought to demonstrate waveguides and chip-scale photonic components in which such back-scattering never occurs even in the presence of disorder or defects. Our proposed approach to counteract such backscattering was to break time-reversal symmetry in the medium so that modes for opposite, i.e. time- reversed, propagation are simply not symmetric in energy-momentum space. With support from this grant we were able to demonstrate record setting on-chip optical isolators and new approaches to produce non-reciprocity. Most importantly, we were able to experimentally demonstrate the suppression of Rayleigh backscattering in resonators with broken T-symmetry, in both on-chip and off-chip scenarios, using a variety of pumping approaches.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Mar 05, 2024
Accession Number
AD1230691

Entities

People

  • Gaurav Bahl

Organizations

  • University of Illinois Urbana–Champaign

Tags

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Microwave Engineering.
  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.

Technology Areas

  • Space