title: Effective bandwidth reduction for a high-power laser-diode array by an external-cavity technique.
abstract: bandwidth of a high-power laser-diode array was effectively suppressed by use of an off-axis external-cavity technique. The external cavity consisted of a beam-transformation system and a pair of off-axis volume Bragg gratings. During operation at a drive current of 40 A, we reduced the bandwidth's full width at half-maximum from 3.3 to 0.24 nm (14-fold reduction) and achieved an output power of 20 W, or as much as 87% of the power radiated by a free-running laser-diode array without an external cavity.
authors.affiliation: Central Research Laboratory, Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamamatsu, Shizuoka 434-8601, Japan. y-zheng@crl@crl.hpk.co.jp
authors.forename: Yujin
authors.initials: Y
authors.lastname: Zheng
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Kan