The spatiotemporal evolutions of ultrashort pulses in two dimensions are investigated numerically by solving the coupled Maxwell-Bloch equations without invoking the slowly varying envelope approximation and rotating-wave approximation. For an on-axis 2nπ sech pulse, local delay makes the temporal split 2π sech pulses crescent-shaped in the transverse distribution. Due to the transverse effect, the temporal split 2π sech pulses become unstable and experience reshaping during the propagation process. Then, interference occurs between the successive crescent-shaped pulses and multiple self-focusing can form.
|Number of pages||5|
|Journal||Physical Review A - Atomic, Molecular, and Optical Physics|
|Publication status||Published - 30 Dec 2008|