Researchers from the Sandia National Laboratories' Center for Compound Semiconductor Science and Technology in Albuquerque, N.M., have constructed a monolithic coupled-resonator vertical-cavity laser that produces up to 6.1 mW of output in single-fundamental-mode operation.As reported in the Dec. 17 issue of Applied Physics Letters, the laser combines an ion-implanted top cavity and a selectively oxidized bottom cavity to produce the high output with side-mode suppression ratios greater than 30 dB. The researchers hope to someday achieve fundamental TEM00 mode operation with the laser, thus making it suitable for applications such as data communications, laser printing and optical read/write heads.