Optical characteristics of multitransverse-mode two-dimensional vertical-cavity top surface-emitting laser arrays

We observe for the first time up to nine transverse modes lasing in the individual elements of a two-dimensional vertical-cavity top surface-emitting laser array under pulsed operation. These modes consist of the TEM_0,0, TEM_0,1, TEM_1,0, TEM_1,1, TEM_0,2, TEM_2,0, TEM_1,2 , TEM_2,1, and TEM_2,2 modes, Each of these modes couples coherently across the array to form very distinct supermodes. The transverse modes as well as the resulting supermodes are identified by examining the near-field and far-field profiles as well as the corresponding spectra. We also obtain a record 1.4 W (pulsed) of coherent output power from the array during multitransverse-mode operation. In addition, the polarization properties of the array are investigated, It is found that the TEM_0,1 mode is horizontally polarized along the [011] crystalline axis while all the other modes are dominantly vertically polarized along the [011¯] axis