A novel GaInAsP microcylinder laser with AlInAs(O/sub x/) claddings

We have proposed and demonstrated a novel 1.5-/spl mu/m-GaInAsP microcylinder laser with low refractive index InAlAs(O/sub x/) claddings, which allows the strong optical confinement as in a microdisk. The effective threshold current density was 25% lower than that for the previous 0.98-/spl mu/m-GaInAs device. The selective oxidation of the claddings is expected to further reduce the threshold and extend the feasibility of this type of device in large scale photonic circuits.