Theoretical Analysis of ESA-Enhanced 2.8 μm Lasing in Er-Doped ZBLAN Fiber Lasers

Gain-switched 2.8 μm fluoride fiber laser pumped at 1550 nm

“…The relatively low efficiency was due to the cladding-pumping, strong green fluorescence and low pump pump energy (the current maximum pump pulse energy was only 52 µJ). [21] shows a potential of the longer-wavelength pumping for power scaling of 2.8 µm laser. Very recently, 2.8 µm fiber laser core-pumped at 1.7 µm, with an efficiency of 23.7%, shows that the large 1.7 µm ESA crosssection is the key to power scaling [19].…”

“…The long lifetimes allow storing the remaining energy in the level 4 I 11/2 , and the recycling improves slightly compared to the CW operation due to the imbalance of the energy in both laser levels, resulting in increased efficiency. Note that the ETU 1 is the key to achieve the population inversion because the ESA is very weak [21]. The inset of figure 2(a) was the profile pump pulse with a power of 5.2 W and the profile show signs of saturation [22].…”

Intense up-conversion luminescence from Dy3+-doped multi-component telluroborate glass matrix: Role of CuO nanoparticles embedment

“…Bandgap energy (E g ) plays a vital role in determining the optical properties of materials [ 43 ]. Thus, other optical properties of the glass samples herein were derived from their corresponding bandgap energies, and their variation is responsive to the variation of the bandgap energies.…”

Watt-level 2.94μm Er: ZBLAN fiber laser with low threshold

“…% Er-doped double-clad fiber supplied by Le Verre Fluoré features a 0.12 NA, D-shaped pump cladding of 240 μm×260 μm with a core diameter of 16.5 μm. The loss parameters of the fiber at the wavelengths of 980 nm and 2.94 µm are reported as 100 dB/km and 21 dB/km, respectively [7] . Both the high-reflector (HR) and the low-reflector (LR) fiber Bragg gratings (FBGs) were inscribed directly in the doped fiber using femtosecond pulses, as described in the reference.…”