The behavior of self-polarization emission in Nd∶Y_(3)Al_(5)O_(12)(YAG)=Cr^(4+)∶YAG lasers has been proved in some cases.However,the degree and direction of polarization were often sensitive and unstable.We experime...The behavior of self-polarization emission in Nd∶Y_(3)Al_(5)O_(12)(YAG)=Cr^(4+)∶YAG lasers has been proved in some cases.However,the degree and direction of polarization were often sensitive and unstable.We experimentally observed different beam profiles versus the angle of the polarizer relative to the polarization direction of the laser.In order to explore the polarization mechanism,the dynamics of intracavity polarized eigenmodes was analyzed theoretically.Simulative results were well consistent with our experimental observations.It indicated that the linear self-polarization emission was a composite state rather than an intrinsic state.This study contributed to the improvement of the polarization stability in Nd∶YAG=Cr^(4+)∶YAG passively Q-switched lasers.展开更多
End-pumped by a 976 nm diode laser,a high-repetition-rate Er:Yb:YAl3(BO3)4 microchip laser passively Q-switched by a Co2+:MgAl2 O4 crystal is reported.At a quasi-continuous-wave pump power of 20 W,a 1553 nm passively ...End-pumped by a 976 nm diode laser,a high-repetition-rate Er:Yb:YAl3(BO3)4 microchip laser passively Q-switched by a Co2+:MgAl2 O4 crystal is reported.At a quasi-continuous-wave pump power of 20 W,a 1553 nm passively Q-switched laser with the repetition rate of 544 kHz,pulse duration of 8.3 ns,and pulse energy of 3.9 μJ was obtained.To the best of our knowledge,the 544 kHz is the highest reported value for the 1.5 μm passively Q-switched pulse laser.In the continuous-wave pumping experiment,the maximum repetition rate of 144 kHz with the pulse duration of 8.0 ns and pulse energy of 1.7 μJ was obtained at the incident pump power of 6.3 W.展开更多
We observe a nonlinear response of a dual-wavelength Nd：YAG laser when subjected to low-frequency periodic modulations of cavity losses. The modulation frequency is far from the relaxation oscillation frequency. The ...We observe a nonlinear response of a dual-wavelength Nd：YAG laser when subjected to low-frequency periodic modulations of cavity losses. The modulation frequency is far from the relaxation oscillation frequency. The harmonic resonances of the two laser wavelengths associated with antiphase intensity oscillations are demon- strated and resonances up to the fourth order were observed. For relatively weak modulation, the intensity oscillation frequency of the laser is equal to the modulation frequency. Harmonic resonances occur under a stronger modulation. We find that more harmonic components appear when the modulation frequency is increased. Furthermore, with enhancing the modulation, the dominant frequency of the intensity oscillations of both wavelengths is shifted toward the higher-order harmonic frequency.展开更多
In this paper,the frequency difference of the eigen polarization modes of the Nd:YAG crystal laser at different polarization ratios is experimentally studied,and to the best of our knowledge,the correlation between th...In this paper,the frequency difference of the eigen polarization modes of the Nd:YAG crystal laser at different polarization ratios is experimentally studied,and to the best of our knowledge,the correlation between the frequency difference of the eigenmodes and the output polarization degree is reported for the first time.Combined with the analysis of the polarization beam profile,it is proved that the polarized laser produced by the isotropic crystal is due to the frequency locking of the eigen polarization modes.The weak birefringence in the crystal causes the round-trip phase difference of the orthogonal polarization modes,which leads to the frequency difference between the polarization modes.By the adjustment of the cavity mirror,the anisotropic loss will interact with the round-trip phase difference.The eigen polarization modes can reach frequency degeneration,and then be coherently combined to produce linearly polarized laser output.This work provides a useful reference for understanding the physical mechanism of polarized lasers realized by isotropic crystals.展开更多
基金The National Natural Science Foundation of China(No.90922035)the Knowledge Innovation Program of the Chinese Academy of Sciences(No.KJCX2-EW-H03)Fujian high Technology Research and Development Program(No.2012H0046)
基金supported by the National Natural Science Foundation of China(Nos.61575199,61875199,6197520851761135115)+1 种基金Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB20000000)Science Foundation of Fujian Province(No.2019J02015)。
文摘The behavior of self-polarization emission in Nd∶Y_(3)Al_(5)O_(12)(YAG)=Cr^(4+)∶YAG lasers has been proved in some cases.However,the degree and direction of polarization were often sensitive and unstable.We experimentally observed different beam profiles versus the angle of the polarizer relative to the polarization direction of the laser.In order to explore the polarization mechanism,the dynamics of intracavity polarized eigenmodes was analyzed theoretically.Simulative results were well consistent with our experimental observations.It indicated that the linear self-polarization emission was a composite state rather than an intrinsic state.This study contributed to the improvement of the polarization stability in Nd∶YAG=Cr^(4+)∶YAG passively Q-switched lasers.
基金supported by the National Natural Science Foundation of China (Nos.61875199 and 61975208)Strategic Priority Research Program of the Chinese Academy of Sciences (No.XDB20000000)Science and Technology Service Network Initiative of the Chinese Academy of Sciences (No.KFJ-STS-QYZX-069)。
文摘End-pumped by a 976 nm diode laser,a high-repetition-rate Er:Yb:YAl3(BO3)4 microchip laser passively Q-switched by a Co2+:MgAl2 O4 crystal is reported.At a quasi-continuous-wave pump power of 20 W,a 1553 nm passively Q-switched laser with the repetition rate of 544 kHz,pulse duration of 8.3 ns,and pulse energy of 3.9 μJ was obtained.To the best of our knowledge,the 544 kHz is the highest reported value for the 1.5 μm passively Q-switched pulse laser.In the continuous-wave pumping experiment,the maximum repetition rate of 144 kHz with the pulse duration of 8.0 ns and pulse energy of 1.7 μJ was obtained at the incident pump power of 6.3 W.
基金supported by the Natural Science Foundation of Fujian Province (No. 2013J05106)the Fujian High Technology Research and Development Program (No. 2012H0046)
文摘We observe a nonlinear response of a dual-wavelength Nd：YAG laser when subjected to low-frequency periodic modulations of cavity losses. The modulation frequency is far from the relaxation oscillation frequency. The harmonic resonances of the two laser wavelengths associated with antiphase intensity oscillations are demon- strated and resonances up to the fourth order were observed. For relatively weak modulation, the intensity oscillation frequency of the laser is equal to the modulation frequency. Harmonic resonances occur under a stronger modulation. We find that more harmonic components appear when the modulation frequency is increased. Furthermore, with enhancing the modulation, the dominant frequency of the intensity oscillations of both wavelengths is shifted toward the higher-order harmonic frequency.
基金The National Natural Science Foundation of China(90922035)the Knowledge Innovation Program of the Chinese Academy of Sciences(KJCX2-EW-H03)Fujian High Technology Research and Development Program(2012H0046)
基金supported by the Youth Innovation Promotion Association CAS(No.2022303)the CAS Key Technology Talent Program(No.2022000061)+3 种基金the National Natural Science Foundation of China(Nos.U21A20508,61975208,and 62105334)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(No.YZLY202001)the Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China(Nos.2021ZR203,2020ZZ108,and 2021ZZ118)the Project of Science and Technology of Fujian Province(No.2021H0047)。
文摘In this paper,the frequency difference of the eigen polarization modes of the Nd:YAG crystal laser at different polarization ratios is experimentally studied,and to the best of our knowledge,the correlation between the frequency difference of the eigenmodes and the output polarization degree is reported for the first time.Combined with the analysis of the polarization beam profile,it is proved that the polarized laser produced by the isotropic crystal is due to the frequency locking of the eigen polarization modes.The weak birefringence in the crystal causes the round-trip phase difference of the orthogonal polarization modes,which leads to the frequency difference between the polarization modes.By the adjustment of the cavity mirror,the anisotropic loss will interact with the round-trip phase difference.The eigen polarization modes can reach frequency degeneration,and then be coherently combined to produce linearly polarized laser output.This work provides a useful reference for understanding the physical mechanism of polarized lasers realized by isotropic crystals.
