Method for amplifying laser signals and an amplifier for use in said method

An optical amplifier for the 1.3 .mu.m and 1.55 .mu.m wavelengths comprising:

• a. an amplifying gain medium comprising 0.05 -.mu.m to 500 -.mu.m size crystalline particles of trivalent vanadium (V).sup.3+ -doped laser crystal suspended in a nearly index matching transparent material, and
• b. optical means for exciting said amplifying medium with wavelengths in the absorption region of said V.sup.3+ -doped crystallites.

A laser for the 1.3 .mu.m and 1.55 .mu.m wavelengths comprising:

• a. an amplifying laser medium comprising 0.05-.mu.m to 500-.mu.m size crystalline particles of trivalent vanadium (V.sup.3+)-doped laser crystal suspended in a nearly index matching transparent material,
• b. optical means for exciting said amplifying medium with wavelengths in the absorption region of said (V.sup.3+)-doped crystallites, and
• c. a pair of end mirrors disposed at opposite ends of said amplifying laser medium.

V.sup.3+ doped crystallites of wurtzite structure of formula (A)(M)O.sub.2, (where A.dbd.Li, Na, or K;M.dbd.Al or Ga).

An active medium for use in a laser and an amplifier comprising a single crystal of dielectric material doped with vanadium ions in the trivalent state, the single crystal being a crystal of wurtzite structure of formula (A)(M)O.sub.2, (where A.dbd.Li, Na, or K;M.dbd.Al or Ga).

A laser medium or amplifier medium comprising:

• a. a flexible hollow or solid cylindrical structure with a core diameter ranging from 3 .mu.m for amplification in a single-mode fiber systems up to few mm for multimode fiber systems with a larger outside diameter,
• b. a gain medium comprising V.sup.3+ -doped crystallites of submicron and micron size suspended in an index-matching glass, polymer, plastic, or liquid in the core, and
• c. a structure surrounding the core made of plastic, glass, or polymer material with refractive index lower than the core to trap the radiation inside the core, the inside or the outside of the surrounding structure being coated with a high reflectivity, low loss metallic or dielectric material to enhance amplification and confinement.

An article of manufacture comprising a non-gaseous medium and a plurality of crystalline particles, said non-gaseous medium having an index of refraction that substantially matches that of the crystalline particles, the crystalline particles being dispersed within the non-gaseous medium, being capable of lasing and being selected from the group consisting of Cr.sup.4+ -doped crystalline particles and V.sup.3+ -doped crystalline particles.

An article of manufacture comprising:

• (a) an elongated core, said elongated core comprising a non-gaseous medium and a plurality of crystalline particles, said non-gaseous medium having an index of refraction that substantially matches that of the crystalline particles, the crystalline particles being dispersed within the non-gaseous medium, being capable of lasing and being selected from the group consisting of Cr.sup.4+ -doped crystalline particles and V.sup.3+ -doped crystalline particles;
• and
• (b) a light retaining outer structure surrounding said elongated core.