Abstract: A method and a laser for breaking through the limitation of fluorescence spectrum on laser wavelength is disclosed. The method includes: exciting electrons to a high energy level by pump light, and suppressing an oscillation of radiation light by laser cavity coating, using a laser resonance to enhance a transition probability of an electron-phonon coupling from the high energy level to a multi-phonon coupling level, so as to realize the emission and enhancement of breakthrough fluorescence spectrum and realize the radiation light oscillation, wherein the laser cavity includes an incident mirror, a folding mirror, a tuning element and an exit mirror arranged in sequence along an optical path direction, the laser gain medium is located between an incident mirror and a folding mirror in the laser resonator, and the tuning element is arranged in the laser cavity at a Brewster angle.

Abstract: An effective nonlinear optical coefficient optimization method for langasite group solid solution crystals is disclosed. The langasite group crystal A3BC3D2O14 mainly includes langanite (LGN) crystal, langatate (LGT) crystal and langasite (LGS) crystal. The solid solution crystals are formed by adjusting a component proportion of langasite group crystals with the same structure, so that different ions mix and occupy sites in a polyhedral group, and a polyhedral lattice structure, distortion degree, refractive index and refractive dispersion of the solid solution crystal are changed. The reduction of the phase matching angle and the improvement of the nonlinear optical coefficient are realized, and the effective nonlinear optical coefficient is finally optimized.

Abstract: A kind of all-solid-state high-power slab laser based on phonon band-edge emission, which is comprised of a pumping source, a focusing system, a resonant cavity and a self-frequency-doubling crystal; the said self-frequency-doubling crystal is a Yb-doped RECOB crystal cut into slab shape along the direction of the crystal's maximum effective nonlinear coefficient of its non-principal plane; by changing the cutting direction of the crystal, the phase matching of different wavelengths is realized, thus realizing laser output at the band of 560-600 nm; the said pumping source is a diode laser matrix with a wavelength of 880 nm-980 nm; the input cavity mirror and the output cavity mirror are coated with films to obtain laser output at the band of 560-600 nm; the two large faces of the said self-frequency-doubling crystal is cooled by heat sink and located between the input cavity mirror and the output cavity mirror.

Abstract: A visible-to-ultraviolet band optical frequency converter. The processing period of a nonlinear optical crystal is controlled to provide an additional period phase to meet a phase matching condition so as to realize effective optical frequency conversion. The additional period phase is characterized in that phase gratings periodically arranged according to different refractive indexes are formed in the crystal through technologies, including laser micro-processing, ion etching and the like, a nonlinear frequency conversion inverse process is avoided through the periodic structure damage of the crystals in the phase gratings and an additional period phase is provided, phase mismatch caused by the insufficient double refraction of the nonlinear optical crystal is avoided, and efficient frequency doubling or sum frequency output is realized.

Abstract: A visible ultraviolet band optical frequency converter. The processing period of a nonlinear optical crystal is controlled to provide an additional period phase to meet a phase matching condition so as to realize effective optical frequency conversion. The additional period phase is characterized in that phase gratings periodically arranged according to different refractive indexes are formed in the crystal through technologies, including laser micro-processing, ion etching and the like, a nonlinear frequency conversion inverse process is avoided through the periodic structure damage of the crystals in the phase gratings and an additional period phase is provided, phase mismatch caused by the insufficient double refraction of the nonlinear optical crystal is avoided, and efficient frequency doubling or sum frequency output is realized.

Abstract: A kind of all-solid-state high-power slab laser based on phonon band-edge emission, which is comprised of a pumping source, a focusing system, a resonant cavity and a self-frequency-doubling crystal; the said self-frequency-doubling crystal is a Yb-doped RECOB crystal cut into slab shape along the direction of the crystal's maximum effective nonlinear coefficient of its non-principal plane; by changing the cutting direction of the crystal, the phase matching of different wavelengths is realized, thus realizing laser output at the band of 560-600 nm; the said pumping source is a diode laser matrix with a wavelength of 880 nm-980 nm; the input cavity mirror and the output cavity mirror are coated with films to obtain laser output at the band of 560-600 nm; the two large faces of the said self-frequency-doubling crystal is cooled by heat sink and located between the input cavity mirror and the output cavity mirror.

Abstract: This invention is a kind of electrooptic Q-switch element made of a single crystal and belongs to the application of crystal in electrooptic technology field. The invention consists of electrooptic Q-switch which is made of La3Ga5SiO14 or Nd:La3Ga5SiO14 or the other related crystal materials such as La3Ga5-xAlxSiO14, Sr3Ga2Ge4SiO14, Na2CaGe6O14, Ca3Ga2Ge4O14, La3Ga5.5Nb0.5O14 and La3Ga5.5Ta0.5O14 with the common shape or a specific shape containing Brewster angle as shown in figure. This kind of electrooptic Q-switch can be used in YAG laser and other laser. It overcomes the shortages of the commercial Q-switches, such as the high, un-adjustable, low stable half-wave voltage and great half-wave voltage variation with temperature. The advantage of this kind of electrooptic Q-switch is its low, adjustable, high stable half-wave voltage.

Abstract: The present invention provides an electrooptic Q-switch element made of a single crystal. The invention includes a langasite (LGS) single crystal and a reflection element located on one side of the langasite crystal along the light propagation direction. A light beam penetrates the LGS crystal along the main optical axis, is reflected by the reflection element, and passes through the LGS crystal again, so that the rotation angle of the polarization plane of the light originating from the optical activity is zero degrees. One advantage of the electrooptic Q-switch is its low, adjustable, high stable half-wave voltage. The invention can overcome the problems associated with current commercial Q-switches, such as high, non-adjustable, low stable half-wave voltage and great half-wave voltage variation with temperature.