We demonstrate the fabrication of single-mode optical waveguides on lithium niobate on an insulator (LNOI) by optical patterning combined with chemomechanical polishing. The fabricated LNOI waveguides had a nearly symmetric mode profile of ~2.5 &micr...
High-index contrast lithium niobate waveguides, fabricated by the High Vacuum Vapor-phase Proton Exchange (HiVac-VPE) technique, are very promising for increasing both the optical nonlinear and electro-optical efficiencies of photonic integrated devi...
An approach for filtering the fundamental mode in an integrated optical modulator with multimode waveguides based on etched thin lithium niobate nanofilms is presented. It is shown that metal electrodes can be used as a modal filter to suppress high-...
Highly integrated and stable devices are appealing in optical communication and sensing. This appeal arises from the presence of high refractive index contrast and high-quality waveguides. In this study, we improved the vapor proton exchange (VPE) pr...
We present an optical microfiber-lithium niobate on insulator (MF-LNOI) hybrid waveguide for efficient second-order nonlinear processes. The structure combines the advantages of low-loss fiber and high-nonlinearity waveguide systems. We demonstrate t...
The aim of Lab-on-a-chip systems is the downscaling of analytical protocols into microfluidic devices, including optical measurements. In this context, the growing interest of the scientific community in opto-microfluidic devices has fueled the devel...
Waveguides formed by etching, proton-exchange (PE), and strip-loaded on single-crystal lithium niobate (LN) thin film were designed and simulated by a full-vectorial finite difference method. The single-mode condition, optical power distribution, and...
In this paper, we develop a technique for realizing multi-centimeter-long lithium niobate on insulator (LNOI) waveguides with a propagation loss as low as 0.027 dB/cm. Our technique relies on patterning a chromium thin film coated on the top surface...
In photonic integrated circuits (PICs), optical isolators and circulators are utilized to protect active devices from backscattering and to reroute the optical signal. An optical circulator based on the LNOI platform is required to possess wide bandw...
We studied photonic electric-field sensors using a 1 × 2 YBB-MZI modulator composed of two complementary outputs and a 3 dB directional coupler based on the electro-optic effect and titanium diffused lithium–niobate optical waveguides. Th...
In the field of modern optical communication, radar signal processing and optical sensors, true time delay technology, as a key means of signal processing, can achieve the accurate control of the time delay of optical signals. This study presents a n...
Lithium niobate (LN) materials have become a key platform for constructing core optoelectronic devices such as electro-optic (EO) modulators, optical frequency combs, and integrated optical waveguides, owing to their broad transparent window, mature...
Low-loss photonic waveguides in lithium niobate offer versatile functionality as nonlinear frequency converters, switches, and modulators for integrated optics. Combining the flexibility of laser processing with liquid phase epitaxy we have fabricate...
This paper systematically investigates the structural design and numerical characterization of ultra-compact low-loss waveguide bends on lithium niobate-on-insulator (LNOI) thin films via 3D-FDTD simulations. Six 90° bend architectures are analyz...
Electro-optic modulators (EOMs) are pivotal in bridging electrical and optical domains, essential for diverse applications including optical communication, microwave signal processing, sensing, and quantum technologies. However, achieving the trifect...
The thin-film lithium niobate platform, which is emerging as a promising photonic integration platform, currently lacks a polarization-insensitive grating coupler (GC), a crucial component for polarization-independent fiber interfaces. This limitatio...
The results of an experimental study of the abnormal domain structure kinetics in lithium niobate single crystals with a surface layer modified by soft proton exchange are presented. Domain switching in a wide field range allowed two qualitatively di...
Integrated optics is a field of study and technology that focuses on the design, fabrication, and application of optical devices and systems using integrated circuit technology. It involves the integration of various optical components, such as waveg...
Lithium niobate thin film represents as an ideal material substrate for quantum photonics due to its strong electro-optic effect and high-speed modulation capability. Here, we propose a novel platform which heterogeneously integrates single self-asse...
It is shown that the termination of the channeling of the fundamental radiation mode in the waveguide can be observed upon heating of an optical integrated circuit based on proton exchange channel waveguides formed in a lithium niobate single crystal...
Stimulated Brillouin scattering (SBS) lasers based on silicon waveguides with large SBS gain have been widely used in frequency tunable laser emissions, mode-locked pulse lasers, low-noise oscillators, optical gyroscopes and other fields. However, am...
We report the fabrication and optical characterization of Yb3+-doped waveguide amplifiers (YDWA) on the thin film lithium niobate fabricated by photolithography assisted chemo-mechanical etching. The fabricated Yb3+-doped lithium niobate waveguides d...
The integration of a photodetector that converts optical signals into electrical signals is essential for scalable integrated lithium niobate photonics. Two-dimensional materials provide a potential high-efficiency on-chip detection capability. Here,...
In this work, we report on an investigation of the ytterbium diffusion characteristics in lithium niobate. Ytterbium-doped substrates were prepared by in-diffusion of thin metallic layers coated onto x- and z-cut congruent substrates at different tem...
Fiber-chip edge couplers can minimize mode mismatch in integrated lithium niobate (LiNbO3) photonics via facilitating broad optical bandwidth coupling between optical fibers and waveguide circuits. We designed a high-efficiency multi-tip edge coupler...
In this study, we designed, simulated, and optimized proton exchanged integrated Mach-Zehnder modulators in a 0.5-μm-thick x-cut lithium niobate thin film. The single-mode conditions, the mode distributions, and the optical power distribution of t...
The single-mode microring resonators on lithium niobate thin films were designed and simulated using 2.5-D variational finite difference time domain mode simulations from Lumerical mode Solutions. The single-mode conditions and the propagation losses...
Lithium niobate (LN) is a promising optical material, its micro–nano structures have been applied to fields such as photonic crystals, nonlinear optics, optical waveguides, and so on. At present, lithium niobate structural colors are rarely stu...
A miniature Fourier transform spectrometer is proposed using a thin-film lithium niobate electro-optical modulator instead of the conventional modulator made by titanium diffusion in lithium niobate. The modulator was fabricated by a contact lithogra...
This work is devoted to the study of the pyroelectric effect on the properties of optical waveguides formed in a lithium niobate crystal by proton exchange. In the present work, we studied the cessation effect of the radiation channeling during therm...
Frequency conversion process based on periodically poled thin-film lithium niobate (PPTFLN) has been widely recognized as an important component for quantum information and photonic signal processing. Benefiting from the tight confinement of optical...
Optical modulators were, are, and will continue to be the underpinning devices for optical transceivers at all levels of the optical networks. Recently, heterogeneously integrated silicon and lithium niobate (Si/LN) optical modulators have demonstrat...
We demonstrate efficient and thermally stable second-harmonic generation (SHG) in x-cut thin-film lithium tantalate (TFLT) ridge waveguides via modal phase matching (MPM). The experimental characterizations reveal a normalized conversion efficiency (...
This study proposes and simulates a numerical analysis of a diamond racetrack microring resonator on a lithium niobate thin film, operating at a 1.55 µm wavelength. The single-mode conditions, transmission losses, and waveguide dispersions are...
The α-phase waveguides directly produced in one fabrication step only are well known for preserving both the excellent nonlinear properties and the ferroelectric domains orientation of lithium niobate substrates. However, by using the piezoresp...
In the face of increasingly complex application scenarios, there is an urgent need for (Radio Frequency Identification) RFID systems that are capable of accurately identifying microwave signals of different frequency bands. Based on the acumen detect...
Lithium niobate (LiNbO3) has remarkable ferroelectric properties, and its unique crystal structure allows it to undergo significant spontaneous polarization. Lithium niobate plays an important role in the fields of electro-optic modulation, sensing a...
The systematic influence of signal electrode width on electro-optic bandwidth and insertion loss in L-type traveling-wave lithium niobate modulators has not yet been comprehensively quantified, limiting the parametric engineering design of this devic...
With the increasing sensitivity and accuracy of contemporary high-performance electronic information systems to electromagnetic energy, they are also very vulnerable to be damaged by high-energy electromagnetic fields. In this work, an all-dielectric...
A multi-channel mode-division multiplexing based on a chalcogenide-lithium niobate platform using chalcogenide films with adjustable refractive index is proposed, with the aim of overcoming issues with narrow bandwidth and large crosstalk in conventi...
The thin-film lithium niobate (TFLN)-based electro-optic (EO) modulator is one of the most important devices for optical communications in terms of the advantages of low voltages and large bandwidth. However, the large size of devices limits their ap...
With the rapid development of optical communication and quantum information, the demand for efficient and broadband nonlinear frequency conversion has increased. At present, most single-frequency conversion processes in lithium niobate on insulator (...
Ten picoseconds (200 kHz) ultrafast laser micro-structuring of piezoelectric substrates including AT-cut quartz, Lithium Niobate and Lithium Tantalate have been studied for the purpose of piezoelectric devices application ranging from surface acousti...
Ion exchange in glass has a long history as a simple and effective technology to produce gradient-index structures and has been largely exploited in industry and in research laboratories. In particular, ion-exchanged waveguide technology has served a...
A single-frequency narrow linewidth green laser at 510 nm is a vital component for the study of Cesium Rydberg atoms. Here, we demonstrate a 510 nm laser based on single-pass second-harmonic generation (SHG) and sum-frequency generation (SFG) via wav...
In signal processing of the growing semaphore, a microwave photonic filter (MPF) is capable of dealing with high-frequency signals, offering the advantages of high bandwidth, easy tuning, and more. This paper presents an efficient tunable microwave p...
With the increasing communication frequencies in 6G networks, high-speed terahertz (THz) modulation signal generation has become a critical research area. This study first proposes an on-chip high-speed THz modulation signal generation system based o...
With the ever-growing demand for high-speed optical communications, microwave photonics, and quantum key distribution systems, compact electro-optic (EO) modulators with high extinction ratios, large bandwidth, and high tuning efficiency are urgently...
A three-dimensional (3D) electric field sensing scheme is proposed and experimentally demonstrated based on an integrated lithium niobate on insulator (LNOI) platform. The 3D measurement is realized by packing three LNOI-based sensor chips in a trian...
The refractive index change obtained after annealed proton exchange (APE) in lithium niobate (LiNbO3) crystals depends on both the proton exchange process carried out in hot acid and the structure of the crystals. In devices produced by the APE metho...
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