980 nm spread index laser with strain compensated InGaAs/GaAsP/InGaP and 90% fibre coupling efficiency

Abstract
Single transverse and lateral mode InGaAs/GaAsP/InGaP 980 nm SPIN (spread index) ridge waveguide lasers (3 µm × 750 µm) with symmetric far fields of thetas⊥ × thetas|| = 17° × 15°, slope efficiency of ηext = 0.9 W/A and threshold current of Ith = 24 mA have been demonstrated. 90% coupling to singlemode lensed fibre and 52% direct buttcoupling to cleaved fibre has been achieved.