Fiber structure, pulse laser device, supercontinuum light source, and production method for fiber structure

A production method for a fiber structure comprising:

• a first step of preparing a sheet-shaped saturable absorption material and first and second optical fibers;
• a second step of forming a sheet-shaped saturable absorber by punching the saturable absorption material;
• a third step of adsorbing the saturable absorber with an adsorption instrument;
• a fourth step of placing the saturable absorber adsorbed by the adsorption instrument in a tip portion of the first optical fiber;
• and
• a fifth step of causing the tip portion of the first optical fiber and a tip portion of the second optical fiber to butt such that the saturable absorber is sandwiched between the tip portion of the first optical fiber and the tip portion of the second optical fiber, wherein
• each of the tip portions of the first optical fiber and the second optical fiber has a core, a cladding provided around the core, and a ferrule provided around the cladding,
• the tip portion of the first optical fiber has a protruding shape protruding to a tip side,
• in the fourth step, the saturable absorber is placed in the tip portion of the first optical fiber such that an adhering part at least adhering to the core of the first optical fiber and a non-adhering part present around the adhering part and not adhering to the tip portion of the first optical fiber are formed in the saturable absorber,
• in the fourth step, the saturable absorber is placed in the tip portion of the first optical fiber such that the adhering part adheres to the core and the cladding of the first optical fiber, and
• in the fifth step, the tip portion of the first optical fiber and the tip portion of the second optical fiber are caused to butt such that a dent corresponding to a shape of the cladding of the first optical fiber adhering at the adhering part is formed in the saturable absorber.