Apparatus and method for an erbium-doped fiber for high peak-power applications
US7570856B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 7, 2006 |
| Grant date | Aug 4, 2009 |
| Priority date | — |
| Expiry date | Dec 7, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/06729
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method and apparatus using a gain medium in the form of a multiply clad gain fiber having an erbium-doped core. In some embodiments, aluminum and germanium are added to the silica core to make λ0 longer than the signal wavelength so the signal incurs normal dispersion. Optionally, a large-mode-area core amplifies primarily only one low-order mode because its NA is reduced by lowering the core's index of refraction (e.g., by adding fluorine) and/or by raising the index of the silica inner core (e.g., by adding germanium). Optionally, a thulium-doped region provides substantial loss at the first Raman-gain peak with respect to the signal wavelength but minimal loss at the signal or pump wavelength. Optionally, an inner cladding with a higher NA contains pump light within the outer boundaries of the cladding while allowing pump light to enter the core. In some embodiments, a triple cladding is provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.