  Coherent combination of emission power from an array of coupled semiconductor
lasers operating on the same chip is of fundamental and technological
importance. In general, the nonlinear competition among the array supermodes
can entail incoherence and spectral broadening, leading to spatiotemporally
unstable and multimode emission pattern and thus poor beam quality. Here, by
harnessing notions from supersymmetric (SUSY) quantum mechanics, we report that
the strategic coupling between a class III-V semiconductor microring laser
array with its dissipative superpartner can be used to limit the number of
supermodes available for laser actions to one. We introduce a novel approach
based on second-order SUSY transformation in order to drastically simplify the
superpartner array engineering. Compared to a conventional laser array, which
has multimode spectrum, a SUSY laser array is observed to be capable of
operating in a single (transverse) supermode. Enhancement of the peak output
intensity of the SUSY laser array has been demonstrated with high-efficiency
and lower lasing threshold, compared with a single laser and a conventional
laser array. Our experimental findings pave the way towards broad-area and
high-power light generation in a scalable and stable fashion.

Optics;Applied Physics;Quantum Physics