Evanescent and propagating wave characteristics of the photonic quantum ring laser

We present the wave propagation characteristics of photonic quantum ring la sers with clear evidence of the evanescence-propagation crossover behavior. The data obtained from the fiber probe measurements of 15-36 mum disk size lasers show that the Rayleigh's whispering gallery modes always give rise to the propagation mode, with the crossover ranges of 55-80 mum. The three- dimensional but chiral and broken z-axis symmetry nature of the photonic qu antum ring cavity appears to guarantee such a crossover to the propagation in general. (C) 2001 American Institute of Physics.