The invention relates to a
microsphere laser and a preparation method thereof, the
microsphere laser comprises an
optical fiber, microspheres and a pump
light source, the microspheres are
erbium-
ytterbium co-doped microspheres containing
erbium ions and
ytterbium ions, the number of the microspheres is two, the microspheres are respectively a first
microsphere and a second microsphere, the
diameter of the first microsphere is smaller than that of the second microsphere, and the pump
light source is arranged between the
optical fiber and the pump
light source. A conical area which is gradually shrunk from the two ends to the middle is arranged at the position, close to the center, of the
optical fiber, the first end of the conical area is close to the pump light source, the second end of the conical area is far away from the pump light source, and the two microspheres are located on the upper side and the lower side of the conical area of the optical
fiber respectively. The first microsphere is disposed
proximate a first end of the tapered region to couple with a first end of the optical
fiber, and the second microsphere is disposed
proximate a second end of the tapered region to couple with a second end of the optical
fiber. Through the arrangement form of the two microspheres, the optical fiber and the pump light source, the threshold value is reduced.