All-fiber mode selection technique for multicore fiber laser devices

An optical device comprising:

• a gain section having a plurality of core regions including dopant species configured to absorb incident radiation at a first wavelength and emit radiation at a second wavelength;
• two passive sections attached to the gain section at opposite ends;
• and
• said gain section and said two passive sections comprising an optical cavity which selectively promotes in-phase light emission from the optical cavity such that said light emission from the optical cavity, in a far field, has a singular Gaussian distribution about a longitudinal axis extending from the optical cavity.

An optical device comprising:

• a gain section having a plurality of core regions including dopant species configured to absorb incident radiation at a first wavelength and emit radiation at a second wavelength;
• two passive sections attached to the gain section at opposite ends;
• and
• said gain section and said two passive sections comprising an all-fiber optical cavity which selectively promotes in-phase light emission from the optical cavity.

A method of forming an optical device comprising:

• providing a gain section having a plurality of core regions including dopant species configured to absorb incident radiation at a first wavelength and to emit radiation at a second wavelength;
• determining a length of at least one passive section to be attached to the gain section such that said gain section and said at least one passive section form an optical cavity which selectively promotes in-phase light emission from the optical cavity;
• and
• attaching the gain section to the at least one passive section.