Improvement on spectrum of high power diode laser array

Stabilization and spectrum narrowing of the emission wavelength of high-power diode laser array is demonstrated by a volume Bragg grating (VBG) resonator. The spectral full width half maximum of the output emission was suppressed by VBG cavity from 1.7 nm to 0.4 nm, and the emission wavelength of VBG-locked diode laser array varied slightly with variation of output power and heat sink temperature. Output power of 15.12 W is achieved from VBG-locked diode laser array with a loss of approximately 2% when the injection current is 35 A.