We present a method of both polarization and amplitude modulations on an incident beam to obtain a longitudinally polarized subwavelength-sized optical needle. A 4-f system with a spatial light modulator is used to ge...We present a method of both polarization and amplitude modulations on an incident beam to obtain a longitudinally polarized subwavelength-sized optical needle. A 4-f system with a spatial light modulator is used to generate experimentally a two-mode alternate cylindrical vector beam by polarization modulation, enhancing performance and facilitating implementation. We optimize the beam focusing properties after passing the beam through an annular aperture to obtain amplitude modulation by the simulated annealing algorithm. Numerical results indicate that a sharp focal spot （0.417A） with a long focal depth （8A） and a strong longitudinally polarized field can be easily achieved.展开更多
In this paper, we report a high peak power passively Q-switched laser-diode-end-pumped Nd:YVO_4/Cr^(4+):YAG laser polarized along the C axis, generating 4.23-W average power and 18-kW peak power (144-μJ pulse power) ...In this paper, we report a high peak power passively Q-switched laser-diode-end-pumped Nd:YVO_4/Cr^(4+):YAG laser polarized along the C axis, generating 4.23-W average power and 18-kW peak power (144-μJ pulse power) with 8.0-ns time duration (29.4-kHz repetition rate) at 1064 nm while the pump power is 21.2 W.展开更多
基金supported by the National Natural Science Foundation of China(Nos.61036013,61138003,and 11204141)the support given by Tianjin Municipal Science and Technology Commission(No.11JCZDJC15200),the support provided by Tianjin Municipal Science and Technology Commission(No.12JCYBJC31000)
文摘We present a method of both polarization and amplitude modulations on an incident beam to obtain a longitudinally polarized subwavelength-sized optical needle. A 4-f system with a spatial light modulator is used to generate experimentally a two-mode alternate cylindrical vector beam by polarization modulation, enhancing performance and facilitating implementation. We optimize the beam focusing properties after passing the beam through an annular aperture to obtain amplitude modulation by the simulated annealing algorithm. Numerical results indicate that a sharp focal spot （0.417A） with a long focal depth （8A） and a strong longitudinally polarized field can be easily achieved.
文摘In this paper, we report a high peak power passively Q-switched laser-diode-end-pumped Nd:YVO_4/Cr^(4+):YAG laser polarized along the C axis, generating 4.23-W average power and 18-kW peak power (144-μJ pulse power) with 8.0-ns time duration (29.4-kHz repetition rate) at 1064 nm while the pump power is 21.2 W.
