RESUMO
A diode-pumped Q-switched Er3+:ZBLAN double-clad, single-transverse mode fiber laser is practically realized. The Q-switched laser characteristics as a function of pump power, repetition rate, and fiber length are experimentally investigated. The results obtained show that the Q-switched operation with 46 µJ pulse energy, 56 ns long pulses, and 0.821 kW peak power is achieved at a pulse repetition rate of 10 kHz. To the best of our knowledge, this is the highest-ever demonstrated peak power emitted from an actively Q-switched, single-transverse mode Er3+:ZBLAN fiber laser operating near 2.8 µm.
RESUMO
1000 ppmw Sm3+-doped Ge19.4Sb9.7Se67.9Ga3 atomic % chalcogenide bulk glass and unstructured fiber are prepared. Near- and mid-infrared absorption spectra of the bulk glass reveal Sm3+ electronic absorption bands, and extrinsic vibrational absorption bands, due to host impurities. Fiber photoluminescence, centred at 3.75â µm and 7.25â µm, is measured when pumping at either 1300 or 1470â nm. Pumping at 1470â nm enables the photoluminescent lifetime at 7.3â µm to be measured for the first time which was â¼100 µs. This is the longest to date, experimentally observed lifetime in the 6.5-9â µm wavelength-range of a lanthanide-doped chalcogenide glass fiber.
RESUMO
We demonstrate a maximum gain of 4.6 dB at a signal wavelength of 5.28 µm in a 4.1 µm resonantly pumped Pr3+-doped selenide-based chalcogenide glass fibre amplifier of length 109 mm, as well as a new signal excited-stated absorption (ESA) at signal wavelengths around 5.5 µm. This work to the best of our knowledge is the first experimental demonstration of gain at mid-infrared (MIR) wavelengths in a Pr3+-doped chalcogenide fibre amplifier. The signal ESA of the fibre is attributed to the transition 3H6 â (3F4, 3F3) after the pump ESA (3H5 â 3H6) at a pump wavelength of 4.1 µm, which absorbs the MIR signal at wavelengths of 5.37, 5.51 and 5.57 µm, and so spoils the amplifier's performance at these wavelengths. Thus, this signal ESA should be suppressed in a resonantly pumped Pr3+-doped selenide-based chalcogenide fibre amplifier.