We demonstrate antiguided coupling of two adjacent vertical-cavity surface-
emitting lasers (VCSELs), obtaining a 1x2 phase-locked array at 869 nm. The
lateral index modification required for antiguiding is achieved by a patte
rned 3 nm etch performed between two epitaxial growths. In contrast with pr
ior coupled VCSELs, adjacent antiguided VCSELs can emit in phase and produc
e a single on-axis lobe in the far field. Greater than 2 mW of in-phase out
put power is demonstrated with two VCSELs separated by 8 mu m. Moreover, ph
ase locking of two VCSELs separated by 20 mu m is observed, indicating the
possibility of a promising class of optical circuits based upon VCSELs that
interact horizontally and emit vertically. (C) 1999 American Institute of
Physics. [S0003-6951(99)04050-4].