An efficient pulsed CH3OH terahertz （THz） laser pumped by a TEA CO2 laser is investigated experimentally. To improve photon conversion efficiency and THz laser energy, two cavity configurations of the TEA CO2 laser,...An efficient pulsed CH3OH terahertz （THz） laser pumped by a TEA CO2 laser is investigated experimentally. To improve photon conversion efficiency and THz laser energy, two cavity configurations of the TEA CO2 laser, which is external and semi-external, are evaluated. The pump intensities are about 4.7 MW/cm2 and 1.2 MW/cm2, respectively. Higher pump intensity and more stable single lines are obtained in the external cavity. For the 3.8 J pump energy of the 9P（16） transition in the external cavity, the maximum terahertz output energy with 570.5 μm wavelength at 160 Pa is 431 μJ. With a 6 J energy pulse in terms of a semi-external cavity, a 353 μJ terahertz emission （570.5 μm） is produced. The corresponding photon conversion efficiencies are 1.36% and 0.705%, increasing by a factor of about 2.展开更多
A high energy pulsed terahertz（THz） laser is studied experimentally.The laser cavity simply consists of a quartz glass waveguide,a coated GaAs input window,and a crystal quartz output window.NH3 is filled in the cav...A high energy pulsed terahertz（THz） laser is studied experimentally.The laser cavity simply consists of a quartz glass waveguide,a coated GaAs input window,and a crystal quartz output window.NH3 is filled in the cavity as gain medium,and pumped by an 8-J line-tunable transversely excited atmospheric（TEA） CO_2 laser.When 9R（16） transition acts as the pump line,55.6-mJ THz radiation（90μm） is obtained at 730-Pa NH_3 pressure.The corresponding conversion efficiency is 13.54%.Energy and optimal pressure of amplified spontaneous emission and laser oscillation are compared.展开更多
文摘An efficient pulsed CH3OH terahertz （THz） laser pumped by a TEA CO2 laser is investigated experimentally. To improve photon conversion efficiency and THz laser energy, two cavity configurations of the TEA CO2 laser, which is external and semi-external, are evaluated. The pump intensities are about 4.7 MW/cm2 and 1.2 MW/cm2, respectively. Higher pump intensity and more stable single lines are obtained in the external cavity. For the 3.8 J pump energy of the 9P（16） transition in the external cavity, the maximum terahertz output energy with 570.5 μm wavelength at 160 Pa is 431 μJ. With a 6 J energy pulse in terms of a semi-external cavity, a 353 μJ terahertz emission （570.5 μm） is produced. The corresponding photon conversion efficiencies are 1.36% and 0.705%, increasing by a factor of about 2.
基金supported by the Creative Foundation of Wuhan National Laboratory for Optoelectronics under Grant No.Z080007
文摘A high energy pulsed terahertz（THz） laser is studied experimentally.The laser cavity simply consists of a quartz glass waveguide,a coated GaAs input window,and a crystal quartz output window.NH3 is filled in the cavity as gain medium,and pumped by an 8-J line-tunable transversely excited atmospheric（TEA） CO_2 laser.When 9R（16） transition acts as the pump line,55.6-mJ THz radiation（90μm） is obtained at 730-Pa NH_3 pressure.The corresponding conversion efficiency is 13.54%.Energy and optimal pressure of amplified spontaneous emission and laser oscillation are compared.
