Large spontaneous emission factor of 0.1 in a microdisk injection laser

A large spontaneous emission factor of 0.1 was evaluated in a 1.56 μm-GaInAsP microdisk injection laser operating under continuous-wave condition with a threshold current of 50 μA. Some clear evidence of the large spontaneous emission factor, i.e., superlinear light-current characteristics and nonclamped carrier-current characteristics, were observed. It was confirmed that the matching of the lasing wavelength to the spontaneous emission allowed larger spontaneous emission factor.