Phosphorus doped fiber PDF-5/125 series are specially designed for highly efficient Raman lasers and amplifiers operating in the 1.1-1.6 µm spectral range. The main advantage of phosphorus-doped fiber is a three times higher value of the Raman shift as compared to germanium-doped fibers. This feature allows one to strongly simplify the Raman fiber laser and amplifier design. For example, to construct a high-power laser @ 1480nm required for pumping Er-doped fibers, only two cascades of Raman wavelength transformation are necessary, whereas six cascades are necessary in the case of Ge-doped fibers.
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Phosphorus doped fiber | PDF-5/125-P | PDF-5/125-A |
| Fiber quality parameter, Pf | < 1 | > 1 |
| Core diameter, µm | 5.0 ± 0.5 | 5.0 ± 1 |
| Clad diameter, µm | 125 ± 1 | 125 ± 1 |
| Core NA | 0.17 ± 0.02 | 0.17 ± 0.02 |
| Cutoff wavelength, µm | 0.9 ± 0.2 | 0.9 ± 0.2 |
| Optical loss (1064 nm), dB/km | < 2.0 | < 2.9 |
| Optical loss (1240 nm), dB/km | < 1.2 | < 1.95 |
| Optical loss (1480 nm), dB/km | < 1.0 | < 1.45 |
| Raman gain (1240 nm), dB/km*W | > 5.8 | > 5 |
| Nonconcentricity, µm | < 1 | < 1 |
| Other parameters are available on the request | ||