Recent Progress in Lithium Niobate: Optical Damage, Defect Simulation, and On‐Chip Devices

Abstract

Lithium niobate (LN) is one of the most important synthetic crystals. In the past two decades, many breakthroughs have been made in material technology, theoretical understanding, and application of LN crystals. Recent progress in optical damage, defect simulation, and on‐chip devices of LN are explored. Optical damage is one of the main obstacles for the practical usage of LN crystals. Recent results reveal that doping with ZrO2 not only leads to better optical damage resistance in the visible but also improves resistance in the ultraviolet region. It is still awkward to extract defect characteristics and their relationship with the physical properties of LN crystals directly from experimental investigations. Recent simulations provide detailed descriptions of intrinsic defect models, the site occupation of dopants and the variation of energy levels due to extrinsic defects. LN is considered to be one of the most promising platforms for integrated photonics. Benefiting from advances in smart‐cut, direct wafer bonding and layer transfer techniques, great progress has been made in the past decade for LNs on insulators. Recent progress on on‐chip LN micro‐photonic devices and nonlinear optical effects, in particular photorefractive effects, are briefly reviewed.

Enhancement of Photorefraction in Vanadium-Doped Lithium Niobate through Iron and Zirconium Co-Doping

“…Lithium niobate (LN), due to its excellent properties, has a variety of applications from waveguides and resonators to integrated optical devices and optical modulators to holographic storage [1,2,3,4,5,6,7,8]. Holographic storage has garnered a considerable research interest due to its potential future applications and is studied by many researchers from an extended period.…”

Efficient light coupling between an ultra-low loss lithium niobate waveguide and an adiabatically tapered single mode optical fiber

“…Lithium niobate on insulator (LNOI) is an emerging platform which has shown promising potential for integrated photonics due to its numerous advantages of high refractive-index contrast, wide transparent window (0.35-5 μm), large nonlinear coefficient, and excellent electro-optic characteristics [1][2][3][4][5]. In recent years, photonic devices based on LNOI, including waveguides [6,7], microring resonators [1,8], microdisk resonators [9][10][11], and photonic crystal cavities [12,13] have been developed.…”

Direct Graphene Synthesis on Lithium Niobate Substrate by Carbon Ion Implantation

“…Few studies have focused on graphene/optical crystal, but among those that have , the combination of graphene and Lithium Niobate (LiNbO 3 , LN) is one of the most promising structures for development. LN is a nearly all-around artificial crystal, it has ferroelectric, piezoelectric, pyroelectric, photovoltaic, photoelastic, photorefractive and other properties, and has a wide range of applications unmatched by other crystals, known as "silicon materials in the optical field" (Graca et al, 2012;Boes et al, 2018;He et al, 2019;Kong et al, 2019). Its combination with graphene may have an impact on the quantum properties of twodimensional materials, resulting in new photoelectric properties, which will inevitably have a wide range of potential applications (Jin et al, 2013;Baeumer et al, 2015;Salas et al, 2017a;Salas et al, 2018).…”