Nonreciprocal and Topological Plasmonics

Abstract

Metals, semiconductors, metamaterials, and various two-dimensional materials with plasmonic dispersion exhibit numerous exotic physical effects in the presence of an external bias, for example an external static magnetic field or electric current. These physical phenomena range from Faraday rotation of light propagating in the bulk to strong confinement and directionality of guided modes on the surface and are a consequence of the breaking of Lorentz reciprocity in these systems. The recent introduction of relevant concepts of topological physics, translated from condensed-matter systems to photonics, has not only given a new perspective on some of these topics by relating certain bulk properties of plasmonic media to the surface phenomena, but has also led to the discovery of new regimes of truly unidirectional, backscattering-immune, surface-wave propagation. In this article, we briefly review the concepts of nonreciprocity and topology and describe their manifestation in plasmonic materials. Furthermore, we use these concepts to classify and discuss the different classes of guided surface modes existing on the interfaces of various plasmonic systems.

Quantum tunneling dynamics with robust reciprocity of Bose-Einstein condensate in a quadruple-well potential with synthetic gauge fields

“…Our work explores the effects of all system parameters in the four-well potential system on quantum coherent transport and transport reciprocity, deepens the understanding of the entire system, and provides a dynamic mechanism that controls population transport, which is helpful for further understanding and exploring more complex systems, such as non-reciprocal systems [65][66][67][68]. The design of reciprocal quantum switches also provides useful building blocks for quantum simulation [69,70] and quantum information [71][72][73] applications.…”

Unified Coupled-Mode Theory for Geometric and Material Perturbations in Optical Waveguides

“…A consequence of this choice is that the reference waveguide must be reciprocal, to guarantee orthogonality relations for both leaky and guided modes (we discuss this aspect in Section II-B). Reciprocal waveguides are those with symmetric constitutive tensors [26], and they comprise almost every class of waveguides with the only exception of very exotic ones, such as those subjected to strong magnetic fields or made of magnetized plasmonic media [27]. We remark, however, that reciprocity is required only for the reference waveguide and not for the real one.…”

Magnetoplasmonic Nanoantennas for On-Chip Reconfigurable Optical Wireless Communications

“…Inspiration came from the use of magnetic fields to control light propagation properties, which has been done since 1845 when Michael Faraday observed polarization rotation of linearly polarized light propagating parallel to an applied magnetic field. In the late 1870s, the Reverend John Kerr demonstrated the magneto-optical (MO) effects for linearly polarized light reflected from a magnetized surface. , These MO effects were essential for technological breakthroughs such as high-speed nonreciprocal optical isolators, − filters, data storage, (bio)­sensing, − and spectroscopy , devices. Many of these achievements have been made possible by integrating plasmonic effects, i.e., the resonant coupling of free density charge oscillations with the electric field component of light, with magneto-optical effects at the nanoscale.…”