Pd. Floyd et al., COMPARISON OF OPTICAL LOSSES IN DIELECTRIC-APERTURED VERTICAL-CAVITY LASERS, IEEE photonics technology letters, 8(5), 1996, pp. 590-592
The performance of vertical-cavity lasers (VCL's) employing dielectric
apertures formed by lateral oxidation or wetetch undercutting of an A
lAs layer on a common substrate are compared, Although both device typ
es performed well, extracted optical losses from the wet-etch undercut
structures exceed those of AlAs-oxide apertured lasers, The differenc
e in performance is attributed to optical scattering losses specific t
o the aperture fabrication method, enhanced by loss from the larger in
dex of refraction discontinuity of the air-gap aperture relative to th
e AlAs-oxide aperture.