Dynamics of frequency switching in tunable asymmetric Y-branch lasers

Abstract
Measurements of the frequency switching dynamics of discretely tunable asymmetric Y-branch (AYB) lasers with a single current tuning control are described. It is observed that the switching time depends on the frequency separation of the two switched modes, with faster switching for modes which are further apart. The switch-off time of a mode is faster, as short as 4 ns, while the switch-on time is slower, on the order of 10 nm. It is suggested that this switching behavior can be explained by the spectral transients of the laser during switching. Such AYB lasers can be used in the transmitters of packet-switched wavelength-multiplexed communication networks.