Broadband and Low-Random-Phase-Errors 2 × 2 Optical Switch on Thin-Film Lithium Niobate

Abstract

We propose and demonstrate a broadband and lowrandom-phase-errors 22 optical switch on thin-film lithium niobate platform. The proposed switch is based on a typical Mach-Zehnder interferometer constructed with two 22 3-dB multimode interferometer couplers, two few-mode waveguide (FMW) arms, and corresponding input and output waveguides. The use of FMWs can help to reduce the random phase errors and improve the fabrication tolerances. Over a wide optical bandwidth from 1530 nm to 1605 nm, our typical fabricated switch can work on the desired initial operating state and achieve an extinction ratio mostly larger than ~16 dB. The switching voltage is ~7.3 V. The rise and fall times are 134.4 ns and 8.8 ns, respectively. This work can facilitate the development of optical switches on the lithiumniobate-insulator (LNOI) platform.

On-chip tunable quantum interference in a lithium niobate-on-insulator photonic integrated circuit

“…Because of advances in nanofabrication techniques, waveguide circuits with propagation losses as low as 1 dB m −1 at both visible and near-infrared wavelengths have been realized [10][11][12]. Although the fabrication has yet to reach the same maturity as more established platforms, these advances paved the way for high-performance photonic devices based on LNOI, including EO modulators [13,14], switches [15] and frequency combs [16]. Furthermore, the fabrication of periodically poled waveguides also allows for integration of efficient and high brightness quantum light sources directly on-chip [17].…”

High-performance electro-optic switches with compact multimode interference and Bezier S-bend waveguides

“…Optical switches have emerged as essential solutions to meet these escalating demands and are typically categorized into two primary types based on their operational principles: electro-optic (EO) and thermo-optic (TO) switches [1][2][3][4]. EO switches generally outperform TO switches in terms of lower power consumption, higher modulation efficiency, faster switching speeds, and reduced insertion losses (ILs) [5,6]. As a result, EO switches realized with various material platforms have garnered significant attention.…”

“…Utilizing a LiNbO 3 -based EO switch with either a directional coupler (DC) or a Mach-Zehnder interferometer (MZI) has become increasingly popular due to their distinct characteristics [13,14]. Although the MZI is commonly employed to construct high-performance optical switches with wide optical bandwidth and low driving voltage, random phase errors arising from fabrication complexity and inherent polarization sensitivity make the DC a more appealing choice for modern optical switches [5,7]. Employing strategic manipulation in the design process is crucial to position the DC as a viable alternative to the MZI for versatile switching functionality (SF).…”

Polarization-Insensitive Electrooptic Modulation on Anisotropic Thin-Film Lithium Niobate

“…In recent years, the thin-film lithium niobate (TFLN) platform has attracted widespread attention because it retains the excellent material properties of bulk LN while enabling high-density integration. − When compared with silicon on insulator (SOI), LN’s exceptional Pockels coefficient positions it as an ideal platform for achieving high-performance electrooptic (EO) modulation. A series of devices based on EO modulation were designed on LN platforms including EO modulators, − switches, , frequency comb, isolator, and tunable interleaver . Given the anisotropy of the LN material, its EO modulation generally exhibits a strong polarization dependence, typically performs well in one polarization, and exhibits a poor response to the other.…”