Non-Hermitian multimode interference
Abstract
Multimode interference (MMI) and self-imaging are important phenomena of diffractive optics with major applications in signal processing, beam shaping, and optical sensing. Such phenomena generally arise from interference of normal modes in lossless dielectric guiding structures; however, the impact of spatially inhomogeneous optical gain and loss, which break mode orthogonality and symmetries, has been overlooked. Here we consider MMI in non-Hermitian optical systems, either graded-index or coupled optical waveguide structures, and reveal distinctive features, such as the absence of mirror images and strong sensitivity of self-imaging to perturbations, making MMI in non-Hermitian waveguides of interest in optical sensing.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 24, 2020
- Source ID
- 10.1364/ol.385081
Entities
People
- Liang Feng
- Stefano Longhi
Organizations
- Army Research Office