Semiconductor lasers with unconventional cladding structures for small beam divergence and low threshold current

The role of monolithic integration in advanced laser products

“…The power kinks are caused by higher order mode lasing at high injection current levels. In order to reduce beam divergence without much impact on optical overlap, unconventional cladding structures in which higher refractive index layers are inserted in both the lower and upper cladding layers have been proposed [9,10]. The reported far-field can be as low as 211, however our simulation shows that this approach puts a very tight requirement on growth tolerance, as even a slight deviation from the design specification results in a very different laser performance.…”