RARE EARTH ELEMENT DOPED OPTICAL FIBER, AND METHOD FOR IMPROVING RADIATION RESISTANCE OF RARE EARTH ELEMENT DOPED OPTICAL FIBER

摘要

To provide a novel rare earth element doped optical fiber which includes a rare earth element and phosphorous in a core part, nonetheless has high radiation resistance and is hard to be reduced in gain even when used in an environment where radiation is present.SOLUTION: The rare earth element doped optical fiber includes: a core portion; and a clad portion covering the periphery of the core portion. The core portion includes erbium, ytterbium, phosphorus, and germanium.SELECTED DRAWING: Figure 1