Lithium niobate thin film electro-optic modulator.

The linear electro-optic effect offers a valuable means to control light properties via an external electric field. Lithium niobate (LN), with its high electro-optic coefficients and broad optical transparency ranges, stands out as a prominent material for efficient electro-optic modulators. The recent advent of lithium niobate-on-insulator (LNOI) wafers has sparked renewed interest in LN for compact photonic devices.

Study on the optical mechanism of photorefractive resistance in Zr-doped lithium niobate crystals from first-principle calculations.

Lithium niobate on insulator (LNOI) has attracted widespread interest due to the excellent optical performance of lithium niobate crystals and the integration characteristics of thin film devices. With the improvement of the integration level of photonic integrated chips and the increase in light intensity inside the chip, the impact of optical damage in LNOI on-chip performance has attracted attention. One effective way to suppress the optical damage of lithium niobate is to dope it with Zr to form LiNbO (LiNbO:Zr), which is famous for its high resistance to optical damage from ultraviolet to visible spectrum.

On-chip erbium-ytterbium-co-doped lithium niobate microdisk laser with an ultralow threshold.

Erbium-ion-doped lithium niobate (LN) microcavity lasers working in the communication band have attracted extensive attention recently. However, their conversion efficiencies and laser thresholds still have significant room to improve. Here, we prepared microdisk cavities based on erbium-ytterbium-co-doped LN thin film by using ultraviolet lithography, argon ion etching, and a chemical-mechanical polishing process.

On-chip ytterbium-doped lithium niobate waveguide amplifiers with high net internal gain.

Integrated optical systems based on lithium niobate on insulator (LNOI) have shown great potential in recent years. However, the LNOI platform is facing a shortage of active devices. Considering the significant progress made in rare-earth-doped LNOI lasers and amplifiers, the fabrication of on-chip ytterbium-doped LNOI waveguide amplifiers based on electron-beam lithography and inductively coupled plasma reactive ion etching was investigated.

Integrated ytterbium-doped lithium niobate microring lasers.

Integrated and stable microlasers are indispensable building blocks of micro-photonics. Here, we report the realization of an ytterbium-doped lithium niobate microring laser operating in the 1060-nm band under the pump of a 980-nm-band laser. The monolithic laser has a low threshold of 59.

On-chip ytterbium-doped lithium niobate microdisk lasers with high conversion efficiency.

Integrated optical systems based on lithium niobate on insulator (LNOI) have attracted the interest of researchers. Recently, erbium-doped LNOI lasers have been realized. However, the reported lasers have a relatively lower conversion efficiency and only operate in the 1550 nm band.

On-chip erbium-doped lithium niobate microring lasers.

Lithium niobate on insulator (LNOI), regarded as an important candidate platform for optical integration due to its excellent nonlinear, electro-optic, and other physical properties, has become a research hotspot. A light source, as an essential component for an integrated optical system, is urgently needed. In this Letter, we reported the realization of 1550 nm band on-chip LNOI microlasers based on erbium-doped LNOI ring cavities with loaded quality factors higher than 1 million at ∼970, which were fabricated by using electron beam lithography and inductively coupled plasma reactive ion etching processes.

Correction: Saeed, S., et al. Enhancement of Photorefraction in Vanadium-Doped Lithium Niobate through Iron and Zirconium Co-Doping. Materials 2019, Vol. 12, 3143.

The authors wish to make the following corrections to this paper [...

Interaction between Mo and intrinsic or extrinsic defects of Mo doped LiNbO from first-principles calculations.

Lithium niobate (LiNbO, LN) plays an important role in holographic storage, and molybdenum doped LiNbO (LN:Mo) is an excellent candidate for holographic data storage. In this paper, the basic features of Mo doped LiNbO, such as the site preference, electronic structure, and the lattice distortions have been explored from first-principles calculations. Mo substituting Nb with its highest charge state +6 is found to be the most stable point defect form.

Microdisk resonators with lithium-niobate film on silicon substrate.

In this paper, we report the fabrication of lithium niobate (LN) microdisk resonators on a pulsed-laser deposited polycrystalline LN film on a silicon substrate rather than commercially provide LN film on insulator. The quality factor of these polycrystalline LN microdisks were measured above 3.4×10 in the 1550-nm band.

Linear Tuning of Phase-Matching Temperature in LiNbO:Zr Crystals by MgO Co-Doping.

We grew a series of co-doped LiNbO crystals with fixed 1.5 mol % ZrO and various MgO concentrations (1.0, 3.

p-Type conductivity mechanism and defect structure of nitrogen-doped LiNbO from first-principles calculations.

Most metal-doped lithium niobates (LiNbO3, LN) exhibit n-type conductivity. The absence of p-type conductive LiNbO3 limits its application. Based on the finding that p-type conductive LiNbO3 can be realized by doping with a non-metallic element N, we investigate the most stable defect configurations and formation energies of LiNbO3 doped with non-metal nitrogen (LN:N) by first-principles calculations.

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

A series of mono-, double-, and tri-doped LiNbO crystals with vanadium were grown by Czochralski method, and their photorefractive properties were investigated. The response time for 0.1 mol% vanadium, 4.

Fabrication and Characteristics of Heavily Fe-Doped LiNbO/Si Heterojunction.

A series of heavily Fe-doped LiNbO (LN:Fe) crystals were grown via the Czochralski method. The dark- and photo-conductivity of the 5.0 wt.

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

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.

P-Type Lithium Niobate Thin Films Fabricated by Nitrogen-Doping.

Nitrogen-doped lithium niobate (LiNbO₃:N) thin films were successfully fabricated on a Si-substrate using a nitrogen plasma beam supplied through a radio-frequency plasma apparatus as a dopant source via a pulsed laser deposition (PLD). The films were then characterized using X-Ray Diffraction (XRD) as polycrystalline with the predominant orientations of (012) and (104). The perfect surface appearance of the film was investigated by atomic force microscopy and Hall-effect measurements revealed a rare p-type conductivity in the LiNbO₃:N thin film.

Effect of Defects on Spontaneous Polarization in Pure and Doped LiNbO₃: First-Principles Calculations.

Numerous studies have indicated that intrinsic defects in lithium niobate (LN) dominate its physical properties. In an Nb-rich environment, the structure that consists of a niobium anti-site with four lithium vacancies is considered the most stable structure. Based on the density functional theory (DFT), the specific configuration of the four lithium vacancies of LN were explored.

The simultaneous enhancement of photorefraction and optical damage resistance in MgO and Bi2O3 co-doped LiNbO3 crystals.

For a long time that optical damage was renamed as photorefraction, here we find that the optical damage resistance and photorefraction can be simultaneously enhanced in MgO and Bi2O3 co-doped LiNbO3 (LN:Bi,Mg). The photorefractive response time of LN:Bi,Mg was shortened to 170 ms while the photorefractive sensitivity reached up to 21 cm(2)/J. Meanwhile, LN:Bi,Mg crystals could withstand a light intensity higher than 10(6)  W/cm(2) without apparent optical damage.