Transition metal disulfides are widely applied as nonlinear optical materials for laser pulse generation.In this paper,TaS_(2)is successfully used for the first time to achieve a high-energy passively Q-switched erbiu...Transition metal disulfides are widely applied as nonlinear optical materials for laser pulse generation.In this paper,TaS_(2)is successfully used for the first time to achieve a high-energy passively Q-switched erbium-doped fiber(EDF)laser.TaS_(2)nanosheets are prepared by the liquid phase exfoliation method,and then the TaS_(2)solution is mixed with polyvinyl alcohol(PVA).TaS_(2)/PVA film is prepared,which is cut into 1 mm×1 mm flakes.TaS_(2)/PVA saturable absorber(SA)is obtained by sandwiching a small flake between two fiber optic patch cable connectors.With the TaS_(2)/PVA SA added to an EDF laser,a Q-switched fiber laser with a center wavelength of 1560 nm and a repetition rate ranging from 51.33 k Hz to 83.04 k Hz is realized.At the pump power of 231 m W,the maximum output power is 1094μW,and the shortest pulse duration is 3.48μs.The results confirm that the TaS_(2)material has excellent potential for application in nonlinear optics.展开更多
The pulsed single-longitudinal-mode(SLM)operation caused by the modal-gain difference in a repetitively passively Q-switched(PQS)laser is studied in detail.Firstly,the analytical expressions for the pulse buildup-time...The pulsed single-longitudinal-mode(SLM)operation caused by the modal-gain difference in a repetitively passively Q-switched(PQS)laser is studied in detail.Firstly,the analytical expressions for the pulse buildup-time difference of repetitively PQS four-level and quasi-three-level lasers have been developed respectively.Then,according to the temporal criterion,the required conditions for repetitively PQS four-level and quasi-three-level lasers to achieve SLM operation are analyzed.The analysis results show that in addition to the short cavity is conducive to obtaining the pulsed SLM laser,the use of a lower pump power(compared to the threshold power)will help to obtain a longer pulse buildup-time difference and thus enabling the SLM operation.Moreover,it is worth noting that for the quasi-three-level lasers,the pulse buildup-time difference also depends on the initial population inversion density.The results also reveal that setting resonator parameters that can obtain large initial population inversion density will be helpful to the SLM operation in both four-level and quasithree-level regimes.In addition,the use of saturable absorber with a low absorption cross-section ratio between the excited state and ground state also contributes to the realization of the SLM.Finally,the optimization model of passively Q-switched single-longitudinal-mode laser is established.In addition to predicting the output performance of the laser,this model can also be used to obtain the optimal resonator parameters and the upper limit of pump power for SLM operation.展开更多
MXenes,drawn from MAX phases,are special two-dimensional substances with numerous advantages in nonlinear optics,specifically in giant and ultrashort pulsed-laser applications.Ti_(3)C_(2)T_(x)and Ti_(2)CT_(x)nanosheet...MXenes,drawn from MAX phases,are special two-dimensional substances with numerous advantages in nonlinear optics,specifically in giant and ultrashort pulsed-laser applications.Ti_(3)C_(2)T_(x)and Ti_(2)CT_(x)nanosheets however rapidly deteriorate under ambient conditions,limiting their applications.This paper demonstrates how excellent modulation depth of one of the MAX phase compounds vanadium zinc carbide(V_2ZnC)makes it a brilliant saturable absorber(SA)in passively Q-switched all-fiber pulsed lasers,integrated such that a 16.73-μm V_(2)ZnC-polyvinyl alcohol(PVA)thin film acts as SA in the laser.Saturable and non-saturable absorptions were found to be 13.2%and 10.47%,while saturation optical intensity and modulation depth were 6.25 k W/cm^(2)and 12.43%,respectively,illustrating the optical nonlinearity.The superiority of MAX-PVA,fabricated in four distinct ratios,was demonstrated by the fact that it self-starts a giant pulsed laser at pump power as low as 22.5 mW and firmly accomplished 120.6 kHz repetition rate with a pulse width of 2.08μs.It is a fine SA for the use of pulsed-laser production using all-fiber laser due to fabrication simplicity and great optical,thermophysical,and mechanical qualities.展开更多
A high-performance LED-side-pumped two-rod Nd,Ce:YAG laser with continuous-wave(CW) and acousto–optical(A-O) Q-switched operation is demonstrated in this work. A symmetrically shaped flat–flat cavity with two identi...A high-performance LED-side-pumped two-rod Nd,Ce:YAG laser with continuous-wave(CW) and acousto–optical(A-O) Q-switched operation is demonstrated in this work. A symmetrically shaped flat–flat cavity with two identical LEDside-pumped laser modules is employed for power scalability. In the CW regime, the maximum output average power of laser at 1064 nm is 4.41 W, corresponding to a maximum optical conversion efficiency of 5.3% and a slope efficiency is 12.4%. In the active Q-switched regime, the pulse energy of laser reaches as high as 0.89 m J at a repetition rate of 800 Hz with a pulse width of 457.2 ns, the corresponding highest peak output power is 1.94 k W and the M~2 factor is measured to be about 8.8. To the best of the authors' knowledge, this is the first demonstration and the highest performance of a CW LED-side-pumped two-rod laser Nd,Ce:YAG with Watt-level output reported so far.展开更多
We propose and demonstrate experimentally a multimode oscillation Q-switched erbium-doped fiber laser with a few-mode fiber cavity. The different coupling processes of reflection peaks of fiber Bragg gratings(FBGs) wh...We propose and demonstrate experimentally a multimode oscillation Q-switched erbium-doped fiber laser with a few-mode fiber cavity. The different coupling processes of reflection peaks of fiber Bragg gratings(FBGs) which act as cavity mirrors allow the different oscillating states. We obtain microsecond light pulse output states whose oscillation and output beams have different mode compositions, including high order mode. Such a structure enables the high order mode oscillation in the whole cavity with an all-fiber structure, which has potential applications in mode-division multiplexed systems and research of multimode nonlinear effect.展开更多
A transmission-type tungsten disulfide（WS_2）-based saturable absorber（SA） is fabricated and applied to passively Q-switched Nd：YVO_4 laser.The WS_2 nanosheets are deposited on a quartz substrate by the vertical e...A transmission-type tungsten disulfide（WS_2）-based saturable absorber（SA） is fabricated and applied to passively Q-switched Nd：YVO_4 laser.The WS_2 nanosheets are deposited on a quartz substrate by the vertical evaporation method.By inserting the WS2 SA into the plano-concave laser cavity,we achieve 153-ns pulses with an average output power of1.19 W at 1064 nm.To the best of our knowledge,both of them are the best results among those obtained by the Q-switched solid-state lasers with WS_2-based absorbers.The repetition rate ranges from 1.176 MHz to 1.578 MHz.As far as we know,it is the first time that MHz level Q-switched pulses have been generated in all solid state lasers based on low-dimensional materials so far.展开更多
We presented a passively Q-switched(PQS) diode-pumped c-cut Tm, Ho:LuVO_4 laser with a black phosphorus saturable absorber for the first time.Under PQS mode, an average output power of 0.86 W and a peak power of 2.32 ...We presented a passively Q-switched(PQS) diode-pumped c-cut Tm, Ho:LuVO_4 laser with a black phosphorus saturable absorber for the first time.Under PQS mode, an average output power of 0.86 W and a peak power of 2.32 W were acquired from the Tm, Ho:LuVO4 laser with the pump power of 14.55 W, corresponding to a pulse width of 2.89 μs,a pulse repetition rate of 71.84 kHz, and a pulse energy of about 6.70 μJ.展开更多
A diode-end-pumped Q-switched high-efficiency Nd, Cr：YAG laser with simultaneous dual-wavelength emission at 946nm and 1.3μm is demonstrated. The maximum output power of 1.93 W with simultaneous dual-wavelength oper...A diode-end-pumped Q-switched high-efficiency Nd, Cr：YAG laser with simultaneous dual-wavelength emission at 946nm and 1.3μm is demonstrated. The maximum output power of 1.93 W with simultaneous dual-wavelength operation is achieved at an absorbed pump power of 13.32 W and an absorbed slope efficiency of 15.15%. The maximum optical-optical efficiency is 14.49% with pulse widths of 16.38ns at 946nm and 26.65ns at 1.3μm. A maximum total repetition rate of 43.25 kHz is obtained.展开更多
We report the repetitively Q-switched laser operation of the Yb-doped calcium niobium gallium garnet disordered garnet crystal, achieved with an acousto-optic modulator in a compact plano-concave resonator that is end...We report the repetitively Q-switched laser operation of the Yb-doped calcium niobium gallium garnet disordered garnet crystal, achieved with an acousto-optic modulator in a compact plano-concave resonator that is endpumped by a 935-nm diode laser. An average output power of 1.96 W is produced at pulse repetition rate of50 k Hz at emission wavelengths around 1035 nm, with a slope efficiency of 16%. The highest pulse energy of 269 μJ is generated at pulse repetition rate of 1 k Hz, with pulse width 12.1 ns and peak power 20.53 kW.展开更多
We demonstrate a middle infrared ZnGeP_2 optical parametric oscillator pumped by the Q-switched Ho：GdVO_4 laser. When the incident Ho pump power is 4.12 W, the maximum average output power of the ZGP-OPO laser is 2.0...We demonstrate a middle infrared ZnGeP_2 optical parametric oscillator pumped by the Q-switched Ho：GdVO_4 laser. When the incident Ho pump power is 4.12 W, the maximum average output power of the ZGP-OPO laser is 2.05 W, corresponding to a slope efficiency of 74.6%. The ZGP-OPO laser produces 4.2 ns mid-infrared pulses at a pulse repetition rate of 5 kHz. In addition, we obtain 0.8 um of tunable range for the signal wave and 2.1 um of tunable range for the idler wave.展开更多
We demonstrate a Q-switched ytterbium-doped fiber laser （YDFL） using a newly developed multi-layer black phosphorous （BP） saturable absorber （SA）. The BP SA is prepared by mechanically exfoliating a BP crystal a...We demonstrate a Q-switched ytterbium-doped fiber laser （YDFL） using a newly developed multi-layer black phosphorous （BP） saturable absorber （SA）. The BP SA is prepared by mechanically exfoliating a BP crystal and sticking the acquired BP flakes onto a scotch tape. A small piece of the tape is then placed between two ferrules and incorporated in a YDFL cavity to achieve a stable Q-switched operation in a 1.0 μm region. The laser has a pump threshold of 55.1 mW, a pulse repetition rate that is tunable from 8.2 to 32.9 kHz, and the narrowest pulse width of 10.8 μs. The highest pulse energy of 328 nJ is achieved at the pump power of 97.6 mW. Our results show that multi-layer BP is a promising SA for Q-switching laser operation.展开更多
We demonstrate a Q-switched Raman fiber laser using molybdenum disulfide （MoS2） as a saturable absorber （SA）. The SA is assembled by depositing a mechanically exfoliated MoS2 onto a fiber ferrule facet before it i...We demonstrate a Q-switched Raman fiber laser using molybdenum disulfide （MoS2） as a saturable absorber （SA）. The SA is assembled by depositing a mechanically exfoliated MoS2 onto a fiber ferrule facet before it is matched with another clean ferrule via a connector. It is inserted in a Raman fiber laser cavity with a total cavity length of about 8kin to generate a Q-switching pulse train operating at 1560.2nm. A 7.7-kin-long dispersion compensating fiber with 584 ps.nm-i km-1 of dispersion is used as a nonlinear gain medium. As the pump power is increased from 395 m W to 422 m W, the repetition rate of the Q-switching pulses can be increased from 132.7 to 137.4 kHz while the pulse width is concurrently decreased from 3.35μs to 3.03μs. The maximum pulse energy of 54.3 nJ is obtained at the maximum pump power of 422 roW. These results show that the mechanically exfoliated MoS2 SA has a great potential to be used for pulse generation in Raman fiber laser systems.展开更多
We demonstrate a cw and actively Q-switched Er：LuAO laser resonantly dual-end-pumped by 1532nm fibre- coupled laser diodes. A maximum cw output power of 1.9W at 1650.3nm is obtained at a pump power of 25.5 W, corresp...We demonstrate a cw and actively Q-switched Er：LuAO laser resonantly dual-end-pumped by 1532nm fibre- coupled laser diodes. A maximum cw output power of 1.9W at 1650.3nm is obtained at a pump power of 25.5 W, corresponding to a slope efficiency of 43.3 %. In the Q-switched regime, the maximum pulse energy of 3.51 mJ is reached at a pulse repetition rate of 100 Hz, a pulse duration of 90.5ns and a pump power of 25.5 W. At the repetition rate of 400 Hz, the output energy is 2.12m J, corresponding to a pulse duration of 125.4 ns.展开更多
A stable Q-switched erbium doped fiber laser emitting at 1558 nm is demonstrated using a cadmium selenide（CdSe） material coated onto a side-polished D-shape fiber as the saturable absorber（SA）. By elevating the in...A stable Q-switched erbium doped fiber laser emitting at 1558 nm is demonstrated using a cadmium selenide（CdSe） material coated onto a side-polished D-shape fiber as the saturable absorber（SA）. By elevating the input pump power from the threshold of 91 mW to the maximum available power of 136 mW, a pulse train with a maximum repetition rate of 57.44 kHz, minimum pulse width of 3.76 us, maximum average output power of7.99 mW, maximum pulse energy of 0.1391 uJ, and maximum peak power of 36.99 mW are obtained. The signalto-noise ratio of the spectrum is measured to be around 75 dB. This CdSe based SA is simple, robust, and reliable,and thus suitable for making a portable pulse laser source.展开更多
A high-power passively Q-switched Nd：YAG laser operating at lll2nm with Cr4＋：yAO as a saturable absorber is demonstrated. Under 808 nm diode-direct pumping, the maximum average output power of 2.73 W is achieved at...A high-power passively Q-switched Nd：YAG laser operating at lll2nm with Cr4＋：yAO as a saturable absorber is demonstrated. Under 808 nm diode-direct pumping, the maximum average output power of 2.73 W is achieved at the pump power of 16.65 W, corresponding to an optical-to-optical conversion efficiency of 16.4%. At the same time, the pulse width, pulse repetition rate, single pulse energy and peak power are 27.2ns, 9 kHz, 303.3#3 and 11.2kW, respectively. As far as we know, the result gives the highest average output power at 1112nm generated by an 808 nm diode-end-pumped Nd：YAG laser.展开更多
We propose and demonstrate a Q-switched erbium-doped fiber laser （EDFL） using an erbium-doped zirconia-alumina silica glass-based fiber （Zr-EDF） as a saturable absorber. As a 16-cm-long Zr-EDF is incorporated into...We propose and demonstrate a Q-switched erbium-doped fiber laser （EDFL） using an erbium-doped zirconia-alumina silica glass-based fiber （Zr-EDF） as a saturable absorber. As a 16-cm-long Zr-EDF is incorporated into a ring EDFL cavity, a stable Q-switching pulse train operating at 1565？nm wavelength is successfully obtained. The repetition rate is tunable from 33.97？kHz to 71.23？kHz by increasing the pump power from the threshold of 26？mW to the maximum of 74？mW. The highest pulse energy of 26.67？nJ is obtained at the maximum pump power.展开更多
Performance of an LD-end-pumped passively Q-switched Nd： YA G/Cr4＋ ： YA G microchip laser operating at 1123 nm is studied. A maximum average output power of 517row with an optical-to-optical conversion efficiency o...Performance of an LD-end-pumped passively Q-switched Nd： YA G/Cr4＋ ： YA G microchip laser operating at 1123 nm is studied. A maximum average output power of 517row with an optical-to-optical conversion efficiency of 12.6% and a slope efficiency of 25.8% is obtained under a pump power of 4.1 W. A minimum pulse width of 1.1 ns with a pulse repetition rate of 20.2kHz is obtained, and the corresponding pulse energy and peak power are 25.6μJ and 23.3kW, respectively. To our knowledge, the 23.3kW peak power is the highest among 1123nm lasers. Additionally, based on the 1123 nm laser, with LBO as the frequency doubler, a 288-mW green-yellow laser at 561 nm is successfully achieved.展开更多
We demonstrate a Q-switched erbium-doped fiber laser （EDFL） using a newly developed zinc oxide- （ZnO） based saturable absorber （SA）. The SA is fabricated by embedding a prepared ZnO powder into a poly（vinyl alc...We demonstrate a Q-switched erbium-doped fiber laser （EDFL） using a newly developed zinc oxide- （ZnO） based saturable absorber （SA）. The SA is fabricated by embedding a prepared ZnO powder into a poly（vinyl alcohol） film. A small piece of the film is then sandwiched between two fiber ferrules and is incorporated in an EDFL cavity for generating a stable Q-switching pulse train. The EDFL operates at 1560.4nm with a pump power threshold of 11.8mW, a pulse repetition rate tunable from 22.79 to 61.43kHz, and the smallest pulse width of 7.00 μs. The Q-switching pulse shows no spectral modulation with a peak-to-pedestal ratio of 62 dB indicating the high stability of the laser. These results show that the ZnO powder has a great potential to be used for pulsed laser applications.展开更多
We report a high repetition frequency, high power stability and low laser noise laser-diode(LD) end-pumped Nd: YAG ceramic passively Q-switched laser at 1123 nm based on a Ti_(3)C_(2)T_(x)-polyvinyl alcohol(PVA) film ...We report a high repetition frequency, high power stability and low laser noise laser-diode(LD) end-pumped Nd: YAG ceramic passively Q-switched laser at 1123 nm based on a Ti_(3)C_(2)T_(x)-polyvinyl alcohol(PVA) film as a saturable absorber(SA). A Brewster polarizer(BP) and a birefringent crystal(BC) are incorporated to enable frequency selection and filtering for the passively Q-switched 1123 nm pulsed laser to improve the power stability and reduce the noise. When the pump power is 5.1 W, an average output power of 457.9 m W is obtained, corresponding to a repetition frequency of 1.09 MHz,a pulse width of 56 ns, a spectral line width of 0.65 nm, a power instability of ±0.92%, and a laser noise of 0.89%.The successful implementation of the “Ti_(3)C_(2)T_(x)-PVA film passively Q-switching” combined with “frequency selection and filtering of BP + BC” technology path provides a valuable reference for developing pulsed laser with high repetition frequency, high stability and low noise.展开更多
In this paper, the effect of injected energy on low energy single longitudinal mode (SLM) pre-lase Q-switched is analyzed and the optimization procedure is shown in detail. Here, taking the Pr:YLF laser as an example ...In this paper, the effect of injected energy on low energy single longitudinal mode (SLM) pre-lase Q-switched is analyzed and the optimization procedure is shown in detail. Here, taking the Pr:YLF laser as an example of low energy laser, and the parameters of Pr:YLF laser by using pre-lase have been shown. Compared with normal Q-switched laser, the single pulse energy reaches 60.16% and the pulse width exceeds 39.73% when the same maximum energy is injected and SLM is achieved in pre-lase. The analysis results show that pre-lase is suitable for low energy laser to obtain SLM and there be an optimal performance to achieve the optimal energy output.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.12075190)the Shaanxi Fundamental Science Research Project for Mathematics and Physics(Grant No.23JSY019)。
文摘Transition metal disulfides are widely applied as nonlinear optical materials for laser pulse generation.In this paper,TaS_(2)is successfully used for the first time to achieve a high-energy passively Q-switched erbium-doped fiber(EDF)laser.TaS_(2)nanosheets are prepared by the liquid phase exfoliation method,and then the TaS_(2)solution is mixed with polyvinyl alcohol(PVA).TaS_(2)/PVA film is prepared,which is cut into 1 mm×1 mm flakes.TaS_(2)/PVA saturable absorber(SA)is obtained by sandwiching a small flake between two fiber optic patch cable connectors.With the TaS_(2)/PVA SA added to an EDF laser,a Q-switched fiber laser with a center wavelength of 1560 nm and a repetition rate ranging from 51.33 k Hz to 83.04 k Hz is realized.At the pump power of 231 m W,the maximum output power is 1094μW,and the shortest pulse duration is 3.48μs.The results confirm that the TaS_(2)material has excellent potential for application in nonlinear optics.
基金Project supported by National Natural Science Foundation of China(Grant No.62205102)。
文摘The pulsed single-longitudinal-mode(SLM)operation caused by the modal-gain difference in a repetitively passively Q-switched(PQS)laser is studied in detail.Firstly,the analytical expressions for the pulse buildup-time difference of repetitively PQS four-level and quasi-three-level lasers have been developed respectively.Then,according to the temporal criterion,the required conditions for repetitively PQS four-level and quasi-three-level lasers to achieve SLM operation are analyzed.The analysis results show that in addition to the short cavity is conducive to obtaining the pulsed SLM laser,the use of a lower pump power(compared to the threshold power)will help to obtain a longer pulse buildup-time difference and thus enabling the SLM operation.Moreover,it is worth noting that for the quasi-three-level lasers,the pulse buildup-time difference also depends on the initial population inversion density.The results also reveal that setting resonator parameters that can obtain large initial population inversion density will be helpful to the SLM operation in both four-level and quasithree-level regimes.In addition,the use of saturable absorber with a low absorption cross-section ratio between the excited state and ground state also contributes to the realization of the SLM.Finally,the optimization model of passively Q-switched single-longitudinal-mode laser is established.In addition to predicting the output performance of the laser,this model can also be used to obtain the optimal resonator parameters and the upper limit of pump power for SLM operation.
基金supported by the Ministry of Higher under Fundamental Research Grant Scheme(No.FRGS/1/2020/TK0/UTM/02/46)Nippon Sheet Glass Grant(No.R.K130000.7343.4B818)。
文摘MXenes,drawn from MAX phases,are special two-dimensional substances with numerous advantages in nonlinear optics,specifically in giant and ultrashort pulsed-laser applications.Ti_(3)C_(2)T_(x)and Ti_(2)CT_(x)nanosheets however rapidly deteriorate under ambient conditions,limiting their applications.This paper demonstrates how excellent modulation depth of one of the MAX phase compounds vanadium zinc carbide(V_2ZnC)makes it a brilliant saturable absorber(SA)in passively Q-switched all-fiber pulsed lasers,integrated such that a 16.73-μm V_(2)ZnC-polyvinyl alcohol(PVA)thin film acts as SA in the laser.Saturable and non-saturable absorptions were found to be 13.2%and 10.47%,while saturation optical intensity and modulation depth were 6.25 k W/cm^(2)and 12.43%,respectively,illustrating the optical nonlinearity.The superiority of MAX-PVA,fabricated in four distinct ratios,was demonstrated by the fact that it self-starts a giant pulsed laser at pump power as low as 22.5 mW and firmly accomplished 120.6 kHz repetition rate with a pulse width of 2.08μs.It is a fine SA for the use of pulsed-laser production using all-fiber laser due to fabrication simplicity and great optical,thermophysical,and mechanical qualities.
基金Project supported by the Fund from Nanjing University of Posts and Telecommunications,China(Grant Nos.JUH219002 and JUH219007)the Key Research and Development Program of Shandong Province,China(Grant No.2021CXGC010202)。
文摘A high-performance LED-side-pumped two-rod Nd,Ce:YAG laser with continuous-wave(CW) and acousto–optical(A-O) Q-switched operation is demonstrated in this work. A symmetrically shaped flat–flat cavity with two identical LEDside-pumped laser modules is employed for power scalability. In the CW regime, the maximum output average power of laser at 1064 nm is 4.41 W, corresponding to a maximum optical conversion efficiency of 5.3% and a slope efficiency is 12.4%. In the active Q-switched regime, the pulse energy of laser reaches as high as 0.89 m J at a repetition rate of 800 Hz with a pulse width of 457.2 ns, the corresponding highest peak output power is 1.94 k W and the M~2 factor is measured to be about 8.8. To the best of the authors' knowledge, this is the first demonstration and the highest performance of a CW LED-side-pumped two-rod laser Nd,Ce:YAG with Watt-level output reported so far.
基金supported by the National Natural Science Foundation of China(Nos.61322510,61640408 and 61775107)the Tianjin Natural Science Foundation(No.16JCZDJC31000)
文摘We propose and demonstrate experimentally a multimode oscillation Q-switched erbium-doped fiber laser with a few-mode fiber cavity. The different coupling processes of reflection peaks of fiber Bragg gratings(FBGs) which act as cavity mirrors allow the different oscillating states. We obtain microsecond light pulse output states whose oscillation and output beams have different mode compositions, including high order mode. Such a structure enables the high order mode oscillation in the whole cavity with an all-fiber structure, which has potential applications in mode-division multiplexed systems and research of multimode nonlinear effect.
基金Project supported by the National Natural Science Foundation of China(Grant No.61378024)
文摘A transmission-type tungsten disulfide（WS_2）-based saturable absorber（SA） is fabricated and applied to passively Q-switched Nd：YVO_4 laser.The WS_2 nanosheets are deposited on a quartz substrate by the vertical evaporation method.By inserting the WS2 SA into the plano-concave laser cavity,we achieve 153-ns pulses with an average output power of1.19 W at 1064 nm.To the best of our knowledge,both of them are the best results among those obtained by the Q-switched solid-state lasers with WS_2-based absorbers.The repetition rate ranges from 1.176 MHz to 1.578 MHz.As far as we know,it is the first time that MHz level Q-switched pulses have been generated in all solid state lasers based on low-dimensional materials so far.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61775053,51572053,51777046,and 61705140)
文摘We presented a passively Q-switched(PQS) diode-pumped c-cut Tm, Ho:LuVO_4 laser with a black phosphorus saturable absorber for the first time.Under PQS mode, an average output power of 0.86 W and a peak power of 2.32 W were acquired from the Tm, Ho:LuVO4 laser with the pump power of 14.55 W, corresponding to a pulse width of 2.89 μs,a pulse repetition rate of 71.84 kHz, and a pulse energy of about 6.70 μJ.
基金Supported by the National Basic Research Program of China under Grant No 2013CB632704
文摘A diode-end-pumped Q-switched high-efficiency Nd, Cr：YAG laser with simultaneous dual-wavelength emission at 946nm and 1.3μm is demonstrated. The maximum output power of 1.93 W with simultaneous dual-wavelength operation is achieved at an absorbed pump power of 13.32 W and an absorbed slope efficiency of 15.15%. The maximum optical-optical efficiency is 14.49% with pulse widths of 16.38ns at 946nm and 26.65ns at 1.3μm. A maximum total repetition rate of 43.25 kHz is obtained.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11274188 and 11574170
文摘We report the repetitively Q-switched laser operation of the Yb-doped calcium niobium gallium garnet disordered garnet crystal, achieved with an acousto-optic modulator in a compact plano-concave resonator that is endpumped by a 935-nm diode laser. An average output power of 1.96 W is produced at pulse repetition rate of50 k Hz at emission wavelengths around 1035 nm, with a slope efficiency of 16%. The highest pulse energy of 269 μJ is generated at pulse repetition rate of 1 k Hz, with pulse width 12.1 ns and peak power 20.53 kW.
基金Supported by the National Natural Science Foundation of China under Grant No 51572053
文摘We demonstrate a middle infrared ZnGeP_2 optical parametric oscillator pumped by the Q-switched Ho：GdVO_4 laser. When the incident Ho pump power is 4.12 W, the maximum average output power of the ZGP-OPO laser is 2.05 W, corresponding to a slope efficiency of 74.6%. The ZGP-OPO laser produces 4.2 ns mid-infrared pulses at a pulse repetition rate of 5 kHz. In addition, we obtain 0.8 um of tunable range for the signal wave and 2.1 um of tunable range for the idler wave.
基金Supported by the University of Malaya under Grant No PG100-2014B
文摘We demonstrate a Q-switched ytterbium-doped fiber laser （YDFL） using a newly developed multi-layer black phosphorous （BP） saturable absorber （SA）. The BP SA is prepared by mechanically exfoliating a BP crystal and sticking the acquired BP flakes onto a scotch tape. A small piece of the tape is then placed between two ferrules and incorporated in a YDFL cavity to achieve a stable Q-switched operation in a 1.0 μm region. The laser has a pump threshold of 55.1 mW, a pulse repetition rate that is tunable from 8.2 to 32.9 kHz, and the narrowest pulse width of 10.8 μs. The highest pulse energy of 328 nJ is achieved at the pump power of 97.6 mW. Our results show that multi-layer BP is a promising SA for Q-switching laser operation.
文摘We demonstrate a Q-switched Raman fiber laser using molybdenum disulfide （MoS2） as a saturable absorber （SA）. The SA is assembled by depositing a mechanically exfoliated MoS2 onto a fiber ferrule facet before it is matched with another clean ferrule via a connector. It is inserted in a Raman fiber laser cavity with a total cavity length of about 8kin to generate a Q-switching pulse train operating at 1560.2nm. A 7.7-kin-long dispersion compensating fiber with 584 ps.nm-i km-1 of dispersion is used as a nonlinear gain medium. As the pump power is increased from 395 m W to 422 m W, the repetition rate of the Q-switching pulses can be increased from 132.7 to 137.4 kHz while the pulse width is concurrently decreased from 3.35μs to 3.03μs. The maximum pulse energy of 54.3 nJ is obtained at the maximum pump power of 422 roW. These results show that the mechanically exfoliated MoS2 SA has a great potential to be used for pulse generation in Raman fiber laser systems.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61308009 and 61405047the China Postdoctoral Science Foundation Funded Project under Grant No 2013M540288+2 种基金the Fundamental Research Funds for the Central Universities under Grant Nos HIT.NSRIF.2014044 and HIT.NSRIF.2015042the Science Fund for Outstanding Youths of Heilongjiang Province under Grant No JQ201310the Heilongjiang Postdoctoral Science Foundation Funded Project under Grant No LBH-Z14085
文摘We demonstrate a cw and actively Q-switched Er：LuAO laser resonantly dual-end-pumped by 1532nm fibre- coupled laser diodes. A maximum cw output power of 1.9W at 1650.3nm is obtained at a pump power of 25.5 W, corresponding to a slope efficiency of 43.3 %. In the Q-switched regime, the maximum pulse energy of 3.51 mJ is reached at a pulse repetition rate of 100 Hz, a pulse duration of 90.5ns and a pump power of 25.5 W. At the repetition rate of 400 Hz, the output energy is 2.12m J, corresponding to a pulse duration of 125.4 ns.
文摘A stable Q-switched erbium doped fiber laser emitting at 1558 nm is demonstrated using a cadmium selenide（CdSe） material coated onto a side-polished D-shape fiber as the saturable absorber（SA）. By elevating the input pump power from the threshold of 91 mW to the maximum available power of 136 mW, a pulse train with a maximum repetition rate of 57.44 kHz, minimum pulse width of 3.76 us, maximum average output power of7.99 mW, maximum pulse energy of 0.1391 uJ, and maximum peak power of 36.99 mW are obtained. The signalto-noise ratio of the spectrum is measured to be around 75 dB. This CdSe based SA is simple, robust, and reliable,and thus suitable for making a portable pulse laser source.
基金Supported by the Natural Science Foundation of Shandong Province under Grant Nos ZR2015FM018 and ZR2014FM028the National Natural Science Foundation of China under Grant No 61475086
文摘A high-power passively Q-switched Nd：YAG laser operating at lll2nm with Cr4＋：yAO as a saturable absorber is demonstrated. Under 808 nm diode-direct pumping, the maximum average output power of 2.73 W is achieved at the pump power of 16.65 W, corresponding to an optical-to-optical conversion efficiency of 16.4%. At the same time, the pulse width, pulse repetition rate, single pulse energy and peak power are 27.2ns, 9 kHz, 303.3#3 and 11.2kW, respectively. As far as we know, the result gives the highest average output power at 1112nm generated by an 808 nm diode-end-pumped Nd：YAG laser.
基金Supported by the Postgraduate Research of Malaysia under Grant No PG098-2014Bthe CSIR of Government of India
文摘We propose and demonstrate a Q-switched erbium-doped fiber laser （EDFL） using an erbium-doped zirconia-alumina silica glass-based fiber （Zr-EDF） as a saturable absorber. As a 16-cm-long Zr-EDF is incorporated into a ring EDFL cavity, a stable Q-switching pulse train operating at 1565？nm wavelength is successfully obtained. The repetition rate is tunable from 33.97？kHz to 71.23？kHz by increasing the pump power from the threshold of 26？mW to the maximum of 74？mW. The highest pulse energy of 26.67？nJ is obtained at the maximum pump power.
基金Supported by the Foundation of Shandong Province under Grant No J13LN28the National Natural Science Foundation of China under Grant No 11304184
文摘Performance of an LD-end-pumped passively Q-switched Nd： YA G/Cr4＋ ： YA G microchip laser operating at 1123 nm is studied. A maximum average output power of 517row with an optical-to-optical conversion efficiency of 12.6% and a slope efficiency of 25.8% is obtained under a pump power of 4.1 W. A minimum pulse width of 1.1 ns with a pulse repetition rate of 20.2kHz is obtained, and the corresponding pulse energy and peak power are 25.6μJ and 23.3kW, respectively. To our knowledge, the 23.3kW peak power is the highest among 1123nm lasers. Additionally, based on the 1123 nm laser, with LBO as the frequency doubler, a 288-mW green-yellow laser at 561 nm is successfully achieved.
基金Supported by the University of Malaya under Grant No PG173-2015B
文摘We demonstrate a Q-switched erbium-doped fiber laser （EDFL） using a newly developed zinc oxide- （ZnO） based saturable absorber （SA）. The SA is fabricated by embedding a prepared ZnO powder into a poly（vinyl alcohol） film. A small piece of the film is then sandwiched between two fiber ferrules and is incorporated in an EDFL cavity for generating a stable Q-switching pulse train. The EDFL operates at 1560.4nm with a pump power threshold of 11.8mW, a pulse repetition rate tunable from 22.79 to 61.43kHz, and the smallest pulse width of 7.00 μs. The Q-switching pulse shows no spectral modulation with a peak-to-pedestal ratio of 62 dB indicating the high stability of the laser. These results show that the ZnO powder has a great potential to be used for pulsed laser applications.
基金Project supported by the Serving Local Special Project of Shaanxi Provincial Department of Education of China (Grant No. 19JC040)the National Natural Science Foundation of China (Grant No. 61905193)。
文摘We report a high repetition frequency, high power stability and low laser noise laser-diode(LD) end-pumped Nd: YAG ceramic passively Q-switched laser at 1123 nm based on a Ti_(3)C_(2)T_(x)-polyvinyl alcohol(PVA) film as a saturable absorber(SA). A Brewster polarizer(BP) and a birefringent crystal(BC) are incorporated to enable frequency selection and filtering for the passively Q-switched 1123 nm pulsed laser to improve the power stability and reduce the noise. When the pump power is 5.1 W, an average output power of 457.9 m W is obtained, corresponding to a repetition frequency of 1.09 MHz,a pulse width of 56 ns, a spectral line width of 0.65 nm, a power instability of ±0.92%, and a laser noise of 0.89%.The successful implementation of the “Ti_(3)C_(2)T_(x)-PVA film passively Q-switching” combined with “frequency selection and filtering of BP + BC” technology path provides a valuable reference for developing pulsed laser with high repetition frequency, high stability and low noise.
文摘In this paper, the effect of injected energy on low energy single longitudinal mode (SLM) pre-lase Q-switched is analyzed and the optimization procedure is shown in detail. Here, taking the Pr:YLF laser as an example of low energy laser, and the parameters of Pr:YLF laser by using pre-lase have been shown. Compared with normal Q-switched laser, the single pulse energy reaches 60.16% and the pulse width exceeds 39.73% when the same maximum energy is injected and SLM is achieved in pre-lase. The analysis results show that pre-lase is suitable for low energy laser to obtain SLM and there be an optimal performance to achieve the optimal energy output.
