Two solutions that achieve high-power (>200mW) diffraction-limited-beam, array operation: 1) Out-of-phase coupled positive index guides, and 2) Closely spaced antiguides

Abstract

Progress in diffraction-limited arrays has been slow. The fundamental-mode beam of evanescently-coupled devices invariably broadens at powers >40 mW, because of the gain spatial hole burning (SHB). Y-junction coupled devices, while immune to gain SHB, have beams 3.5-4 times the diffraction limit due to weak coupling. Here we present two solutions for high-power, diffraction-limited operation: 1) devices operating in array modes stable against gain SHB: and 2) devices immune to game SHB, yet strongly coupled.