Neodymium-doped Yttrium Vanadate-manufacture,factory,supplier from China

Research BackgroundLithium Yttrium Fluoride (LiYF4, YLF) crystal has many excellent properties such as low melting point, low phonon energy, small thermal lens effect, natural polarization, etc. It is a laser matrix material with excellent performance. YLF belongs to the tetragonal structure of scheelite, and the space group is I41/a.

1. 3 2 ~ 3 μm laser crystals doped with Cr2+ The mid-infrared luminescence of transition metal ions (Ni2+, Co2+, Cr2+, Fe2+, etc.) is based on 3d→3d transitions. According to the different types of sites occupied by transition metal ions in the host material, they can be divided into two categories: occupying octahedral sites with inversion symmetry (such as: Ni2+, Co2+ doped halides); Symmetric tetrahedral sites (such as: Ni2+, Co2+, Cr2+, Fe2+ doped II-VI compounds).

1. ~ 2 μm laser crystals doped with Tm3+ or Ho3+Tm3+ has a strong absorption near ~790 nm and a large absorption cross-section, so the ~790 nm commercial LD can be directly used as a pump source.

1.5  ~ 4 μm laser crystals doped with Fe2+ Compared with Cr:ZnSe, Fe:ZnSe has a smaller band gap and is prone to produce thermally induced multi-phonon quenching, so both laser power and efficiency are low. In 1999, Adams et al. realized the tunable wavelength of 3.98-4.54 μm at low temperature for the first time in Fe:ZnSe, and obtained laser output with slope efficiency of 8.2%. Pumped by Er3+ doped or Cr:ZnSe @ 2.7 μm laser, 4.0 μm wavelength and 1 W level continuous laser output have been obtained at room temperature. In 2020, Pushkin et al.

1. 2   ~ 2.3 μm laser crystals doped with Tm3+ Compared with the 2 μm band (3F4 → 3H6) of Tm3+, the 2.3 μm laser operation based on the 3H4 → 3H5 transition of the Tm3+ doped laser medium has the following advantages: (1) ~790 nm LD is directly pumped to the upper energy level of the laser. Tm3+ has a strong absorption around 790 nm (directly corresponding to the 3H4 → 3H6 transition), which can match the emission wavelength of the current mature commercial AlGaAs LD, so as to realize high-performance LD pumping all-solid-state high-efficiency 2.3 μm laser operation.

1. 4  ~ 3 μm laser crystals doped with Er2+, U4+, Ho3+, Dy3+  As an active ion, Ho3+ has achieved laser output in the ~3 μm band (5I6→5I7). In 1976, researchers first realized 2.9 μm laser output in Ho:YAP crystal. In 1990, Bowman et al. obtained 2.85 μm and 2.92 μm laser outputs in Ho:YAP crystals, and obtained 2.92 μm band-tuned laser outputs in Ho:YAP crystals in the following year. In 2017, Nie et al. pumped Ho, Pr: LiLuF4 crystals with a 1 150 nm Raman fiber laser, achieving 2.95 μm watt-level laser output for the first time. In 2018, Zhang et al.

3 The main application of lithium tantalate crystal3.1 SAW Wave filterPeng et al. used ion etching to process lithium tantalate (LT) crystals to obtain a high fundamental frequency crystal resonator. They used this crystal resonator to design a high-frequency broadband filter, which improved the operating frequency and reliability of the filter and increased the number of The bandwidth of the filter ensures the high temperature stability and low insertion loss of the filter.

3.2 Laser Pretreatment TechnologyLaser pretreatment is a technology that uses sub-threshold laser energy flow to process components before they are practically used. It can effectively improve the ability of some optical components to resist laser damage. The main function of laser pretreatment is to remove defects or reduce thermodynamic response under laser irradiation.

3 The main application of lithium tantalate crystal3.4 Pyroelectric detectorTo detect targets, pyroelectric detectors generally exchange heat with the outside environment through three methods: thermal convection, thermal conduction and thermal radiation. The working principle is: electrons are adsorbed on the surface of the pyroelectric material, and the surface is neutral; the temperature of the material surface changes when heated, and the electric dipole moment of the material changes; in order to keep the surface of the material neutral, the surface releases charges.

3 The main application of lithium tantalate crystal3.2 OscillatorAn oscillator is an energy conversion device that converts DC power into AC power with a certain frequency. This circuit is called an oscillation circuit. The oscillator achieves free oscillation through the mutual conversion between magnetic field energy and electric field energy.Oscillators are divided into RC oscillators, LC oscillators and crystal oscillators. The crystal oscillator has a piezoelectric effect, and the crystal will deform when a voltage is applied to the two poles of the wafer.