On-chip coherent combining of angled-grating diode lasers toward bar-scale single-mode lasers

Opt Express. 2012 Mar 12;20(6):6375-84. doi: 10.1364/OE.20.006375.

Abstract

Single mode operation of broad-area diode lasers, which is the key to obtain high power, high brightness sources, is difficult due to highly nonlinear materials and strong coupling between gain and index. Conventional broad-area lasers usually operate with multiple modes and have poor beam quality. Laser bars usually consist of incoherently combined broad-area single emitters placed side by side. In this article, we have demonstrated a novel integrated laser architecture in which Bragg diffraction is used to realize simultaneous modal control and coherent combining of broad-area diode lasers. Our experimental results show that two 100 μm wide, 1.3mm long InP broad-area lasers provide near-diffraction-limited output beam and are coherently combined at the same time without any external optical components. Furthermore, our design can be expanded to a coherently combined broad-area laser array that turns a laser bar into a coherent single mode laser with diffraction-limited beam quality.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Equipment Design
  • Equipment Failure Analysis
  • Lasers, Semiconductor*
  • Refractometry / instrumentation*
  • Systems Integration