All glass fiber laser cladding mode stripper

A system comprising:

• a fiber gain medium having a core and a cladding, the core configured to convert radiation from a pump beam into an output beam, the cladding having a first section and a second section bounded on a near end and a distal end by the first section, excess pump radiation propagating in the first section of the cladding, the second section of the cladding having a beam scattering section including a set of equiangular fins protruding from the cladding, each fin in the set of equiangular fins having a pair of linear walls apart from the outer surface of the cladding and being configured to (1) trap the unconverted radiation and (2) eject the trapped radiation outwardly through the pair of linear walls.

A method of manufacturing a fiber gain medium including a core and a cladding, the core configured to convert pump radiation into an output beam, the method comprising:

• applying a roughening treatment to a piece of passive fiber which has a core and cladding identical to the fiber gain medium and splicing the roughened passive fiber onto the fiber gain medium.