GaSb lasers get pulses racing

Abstract

Near-transform limited optical pulses of 384 fs at 1960 nm have been generated from a passively modelocked gallium-antimonide-based disk laser. Collaborating researchers from Tampere University of Technology in Finland and Max Born Institute (MBI) in Berlin, Germany, developed a fast GaSb-based saturable absorber mirror to modelock the laser and achieved the shortest pulses so far for this material system.“We found it quite surprising that the much more exotic GaSb material platform can deliver components, both on the absorber and the gain side, that can match or even outperform the GaAs material system,” said Antti Härkönen, one of the researchers from Tampere. “This is indicated by both the subpicosecond recovery time of our absorber mirrors as well as the measured pulse duration, which is only 2% larger than the Fourier limit.”