A new approach to improve mode selectivity of higher output oxide-confined vertical-cavity surface-emitting lasers

Abstract

Requirements of a higher output and the single-fundamental-mode operation are usually contradictory to each other. In the present paper, an essential modification of a design of the GaAs-based oxide-confined vertical-cavity surface-emitting lasers (VCSELs) is proposed. Functions of both the oxide apertures are separated: while the larger upper one is designed to create the radial waveguiding effect, the smaller bottom one is only funnelling the current injection into the active region. Hence both may be optimized separately. As a result, single-fundamental-mode operation is confirmed by our simulation to be preserved at much higher output and/or at much higher temperatures than in standard VCSELs.