Interference filter-stabilized external cavity diode lasers （ECDLs） have properties of simple configurations, high sta- bilities, and narrow linewidths. However, the interference filter used in common ECDL designs r...Interference filter-stabilized external cavity diode lasers （ECDLs） have properties of simple configurations, high sta- bilities, and narrow linewidths. However, the interference filter used in common ECDL designs requires an ultra-narrow bandwidth （about 0.3 nm） to achieve mode selection, that is considerably expensive and not yet available for a wide range of wavelengths. In this paper, a robust ECDL using an available broad bandwidth （about 4 nm） interference filter as the wavelength discriminator is constructed and tested. The ECDL demonstrated a narrow Lorentzian fitted linewidth of 95 kHz and a spectral purity of 2.9 MHz. The long-term frequency stability of the ECDL reaches 5.59 x 10 12.展开更多
A 1550-nm linearly tunable continuous wave （CW） single-mode external cavity diode laser （ECDL） based on a singlecavity all-dielectric thin-film Fabry-Pérot filter （s-AFPF） is proposed and realized in this p...A 1550-nm linearly tunable continuous wave （CW） single-mode external cavity diode laser （ECDL） based on a singlecavity all-dielectric thin-film Fabry-Pérot filter （s-AFPF） is proposed and realized in this paper. Its internal optical components as well as their operation mechanisms are introduced first, and then its longitudinal mode output characteristic is theoretically analyzed. Afterwards, we set up the experimental platform for the output characteristic measurement of this tunable ECDL; under different experimental conditions, we execute accurate and real-time measurements for the output central wavelength, output optical power, output longitudinal mode distribution, and the line-width of the tunable ECDL in its tuning process. By summing up the optimal experimental condition from the measured data, we obtain the optimal tunable ECDL relevant parameters： the tunable ECDL has a linear mode-hop-free wavelength tuning region of 1547.203 nm-1552.426 nm, a stable output optical power in the range of 40 μW-50 μW, and a stable output longitudinal mode distribution of a single longitudinal mode with a line-width in the range of 100 MHz-150 MHz. This tunable ECDL can be used in environmental gas monitoring, atomic and molecular laser spectroscopy research, precise measurements, and so on.展开更多
A diode laser array(DLA)positioned in an external cavity can receive the radiations emitted from its neighboring elements (C 1) and that of itself (S) after being reflected at the DLA facet as well as from the externa...A diode laser array(DLA)positioned in an external cavity can receive the radiations emitted from its neighboring elements (C 1) and that of itself (S) after being reflected at the DLA facet as well as from the external mirror (C 0). Considering the fact that｜C 0/S｜ should be larger than unity if the external cavity is effective,and｜C 1/S｜ should be larger than unity if the phase locking may be established in the external cavity.The requirements on the reflection at the facet of the diode laser array have been specified in terms of the cavity length and reflection coefficient of the external mirror.展开更多
In this paper,a spectral beam combining(SBC)structure of multi-single emitters laser diode based on a polarization full feedback(PFF)external cavity is proposed and demonstrated.The maximum combining efficiency is 75....In this paper,a spectral beam combining(SBC)structure of multi-single emitters laser diode based on a polarization full feedback(PFF)external cavity is proposed and demonstrated.The maximum combining efficiency is 75.6%,which leads to an output power of 38.48 W,a degree of polarization(DOP)of 99.42%,and electro-optical conversion efficiency of 35.63%under continuous wave operation at a current of 8 A.Compared to the conventional SBC,the output power,the combining efficiency,the electro-optical conversion efficiency,and the DOP of the PFF-SBC structure present improvements of 5.73 W,11.26 percentage points,5.3 percentage points,and 7.26 percentage points,respectively.The results show that this SBC method can achieve a high efficiency and linearly polarized laser output of SBC,thereby making the subsequent polarization beam-combining efficiency approach the limit.展开更多
In this research,the highly efficient external cavity feedback technology based on volume Bragg grating(VBG)is studied.By using the structure of a fast axis collimating lens,the beam transformation system,a slow axis ...In this research,the highly efficient external cavity feedback technology based on volume Bragg grating(VBG)is studied.By using the structure of a fast axis collimating lens,the beam transformation system,a slow axis collimating lens,and VBG,the divergence angle of the fast and slow axes of the diode laser incident on the VBG is reduced effectively,and the feedback efficiency of the external cavity is improved.Combined with beam combining technology,fiber coupling technology,and precision temperature control technology,a high-power and narrow-linewidth diode laser pump source of kilowatt class is realized for alkali metal vapor laser pumping.The core diameter of the optical fiber is 1000μm,the numerical aperture is 0.22,the output power from the fiber is 1013 W,the fiber coupling efficiency exceeds 89%,and the external cavity efficiency exceeds 91%.The central wavelength is 852.052 nm(in air),which is tunable from 851.956 nm to 852.152 nm,and the spectral linewidth is 0.167 nm.Research results can be used for cesium alkali metal vapor laser pumping.展开更多
We present a compact and practical scheme of building a ~780 nm external cavity diode laser(ECDL) whose wavelength is mainly determined by an interference filter. The Lorentzian linewidth measured by the heterodyne be...We present a compact and practical scheme of building a ~780 nm external cavity diode laser(ECDL) whose wavelength is mainly determined by an interference filter. The Lorentzian linewidth measured by the heterodyne beating between two identical lasers is 60 k Hz, and the geometry size of the laser is only 71.5 mm×65 mm×40 mm. The linear cavity design is less sensitive to misalignment induced by mechanical and thermal disturbances, and in comparison to a common grating-based design, the sensitivity to vibration is substantially reduced. Due to its excellent performance, the laser design has already been applied to cold atom trapping experiments. This interference filter ECDL method can also be extended to other wavelengths and widen the application range of diode laser.展开更多
The self-mixing fringes which shift due to every one-twentieth wavelength displacement of the target are observed. Taking advantage of the dual reflectors in the external cavity of lasers, the resolution of the sensor...The self-mixing fringes which shift due to every one-twentieth wavelength displacement of the target are observed. Taking advantage of the dual reflectors in the external cavity of lasers, the resolution of the sensors has been improved by 10 times. The role of the each reflector has been discussed in detail.展开更多
基金Project supported by the Foundation of Based Technology of China(Grant No.YXBGD20151JL01)the National Natural Science Foundation of China(Grant Nos.61376049,61604007,11674016,61378058,61575008,and 61574011)+1 种基金the Natural Science Foundation of Beijing City,China(Grant Nos.4172009 and4152003)the Beijing Municipal Commission of Education of China(Grant Nos.PXM2017 014204 500034 and PXM2016 014204 500018)
文摘Interference filter-stabilized external cavity diode lasers （ECDLs） have properties of simple configurations, high sta- bilities, and narrow linewidths. However, the interference filter used in common ECDL designs requires an ultra-narrow bandwidth （about 0.3 nm） to achieve mode selection, that is considerably expensive and not yet available for a wide range of wavelengths. In this paper, a robust ECDL using an available broad bandwidth （about 4 nm） interference filter as the wavelength discriminator is constructed and tested. The ECDL demonstrated a narrow Lorentzian fitted linewidth of 95 kHz and a spectral purity of 2.9 MHz. The long-term frequency stability of the ECDL reaches 5.59 x 10 12.
基金the Key Laboratory of Functional Crystals and Laser Technology,Chinese Academy of Sciences(Grant No.JTJG201109)the Guangdong Province&Chinese Academy of Sciences Comprehensive Strategic Cooperation Project(Grant No.2010A090100014)the 2009 Technology Research and Development Fund of Shenzhen,China(Grant No.O702011001)
文摘A 1550-nm linearly tunable continuous wave （CW） single-mode external cavity diode laser （ECDL） based on a singlecavity all-dielectric thin-film Fabry-Pérot filter （s-AFPF） is proposed and realized in this paper. Its internal optical components as well as their operation mechanisms are introduced first, and then its longitudinal mode output characteristic is theoretically analyzed. Afterwards, we set up the experimental platform for the output characteristic measurement of this tunable ECDL; under different experimental conditions, we execute accurate and real-time measurements for the output central wavelength, output optical power, output longitudinal mode distribution, and the line-width of the tunable ECDL in its tuning process. By summing up the optimal experimental condition from the measured data, we obtain the optimal tunable ECDL relevant parameters： the tunable ECDL has a linear mode-hop-free wavelength tuning region of 1547.203 nm-1552.426 nm, a stable output optical power in the range of 40 μW-50 μW, and a stable output longitudinal mode distribution of a single longitudinal mode with a line-width in the range of 100 MHz-150 MHz. This tunable ECDL can be used in environmental gas monitoring, atomic and molecular laser spectroscopy research, precise measurements, and so on.
文摘A diode laser array(DLA)positioned in an external cavity can receive the radiations emitted from its neighboring elements (C 1) and that of itself (S) after being reflected at the DLA facet as well as from the external mirror (C 0). Considering the fact that｜C 0/S｜ should be larger than unity if the external cavity is effective,and｜C 1/S｜ should be larger than unity if the phase locking may be established in the external cavity.The requirements on the reflection at the facet of the diode laser array have been specified in terms of the cavity length and reflection coefficient of the external mirror.
基金This work was supported by the Key Technology Research and Development Program of Shandong(Nos.2022CXGC020104 and 2023ZLYS03)the Key-Area Research and Development Program of Guangdong Province(No.2020B090922003).
文摘In this paper,a spectral beam combining(SBC)structure of multi-single emitters laser diode based on a polarization full feedback(PFF)external cavity is proposed and demonstrated.The maximum combining efficiency is 75.6%,which leads to an output power of 38.48 W,a degree of polarization(DOP)of 99.42%,and electro-optical conversion efficiency of 35.63%under continuous wave operation at a current of 8 A.Compared to the conventional SBC,the output power,the combining efficiency,the electro-optical conversion efficiency,and the DOP of the PFF-SBC structure present improvements of 5.73 W,11.26 percentage points,5.3 percentage points,and 7.26 percentage points,respectively.The results show that this SBC method can achieve a high efficiency and linearly polarized laser output of SBC,thereby making the subsequent polarization beam-combining efficiency approach the limit.
基金This work was supported by the National Natural Science Foundation of China(NSFC)(No.61991433)Pilot Project of CAS(No.XDB43030302)+2 种基金Equipment Pre-research(No.2006ZYGG0304)Key Research and Development Project of Guangdong Province(No.2020B090922003)R&D Program of Jilin Province(No.20190302042GX).
文摘In this research,the highly efficient external cavity feedback technology based on volume Bragg grating(VBG)is studied.By using the structure of a fast axis collimating lens,the beam transformation system,a slow axis collimating lens,and VBG,the divergence angle of the fast and slow axes of the diode laser incident on the VBG is reduced effectively,and the feedback efficiency of the external cavity is improved.Combined with beam combining technology,fiber coupling technology,and precision temperature control technology,a high-power and narrow-linewidth diode laser pump source of kilowatt class is realized for alkali metal vapor laser pumping.The core diameter of the optical fiber is 1000μm,the numerical aperture is 0.22,the output power from the fiber is 1013 W,the fiber coupling efficiency exceeds 89%,and the external cavity efficiency exceeds 91%.The central wavelength is 852.052 nm(in air),which is tunable from 851.956 nm to 852.152 nm,and the spectral linewidth is 0.167 nm.Research results can be used for cesium alkali metal vapor laser pumping.
基金supported by the National Natural Science Foundation of China (No.51275523)the State Key Laboratory of Aerodynamics Research Fund (No.SKLA2019040302)。
文摘We present a compact and practical scheme of building a ~780 nm external cavity diode laser(ECDL) whose wavelength is mainly determined by an interference filter. The Lorentzian linewidth measured by the heterodyne beating between two identical lasers is 60 k Hz, and the geometry size of the laser is only 71.5 mm×65 mm×40 mm. The linear cavity design is less sensitive to misalignment induced by mechanical and thermal disturbances, and in comparison to a common grating-based design, the sensitivity to vibration is substantially reduced. Due to its excellent performance, the laser design has already been applied to cold atom trapping experiments. This interference filter ECDL method can also be extended to other wavelengths and widen the application range of diode laser.
基金Supported by the National Natural Science Foundation of China under Grant No 60438010.
文摘The self-mixing fringes which shift due to every one-twentieth wavelength displacement of the target are observed. Taking advantage of the dual reflectors in the external cavity of lasers, the resolution of the sensors has been improved by 10 times. The role of the each reflector has been discussed in detail.
