Optical Nonreciprocity in Optomechanical Structures

Abstract

We demonstrate that optomechanical devices can exhibit nonreciprocal behavior when the dominant light-matter interaction takes place via a linear momentum exchange between light and the mechanical structure. As an example, we propose a microscale optomechanical device that can exhibit a nonreciprocal behavior in a microphotonic platform operating at room temperature. We show that, depending on the direction of the incident light, the device switches between a high and low transparency state with more than a 20 dB extinction ratio.

Optical Nonreciprocity Based on Optomechanical Coupling

“…(13,14) requires the implementation of system specific -matrices, which are derived in the next section.…”

“…In addition, parametrically coupled multimode systems have been also shown to perform non-reciprocal frequency conversion and amplification [10]- [12], for example based on Josephson junctions [13]. Recently, it has been realized that optomechanical coupling can also be used to impart the required form of synthetic gauge required to induce electromagnetic non-reciprocity at optical [14]- [22] and microwave frequencies [23], [24]. In this context, different theories have been presented to describe possible optomechanical implementations of on-chip isolators [15]- [16], [21]- [22].…”

A Wavelength Selective Bidirectional Isolator

“…Isolators are critical for the development of optical systems, particularly in optical communication system, for example, in PONs (Passive Optical Networks) [1][2][3][4][5]. PON is probably the first FTTx (Fiber to the x) technology, in which unidirection plays a very important role [6].…”

Nonreciprocal Gain in Non-Hermitian Time-Floquet Systems

“…Magnets, however, are bulky, expensive, and to a large extent incompatible with integrated circuit technology and standard CMOS fabrication methods. For this reason, magnet-free non-reciprocal components have been developed based on non-linearity [6][7][8][9][10][11][12][13][14][15][16][17][18] or time-modulation [19][20][21][22][23][24][25][26][27][28][29][30][31][32]. Non-linear systems strongly break reciprocity, however they are fundamentally limited as isolators [33].…”