Angular spectrum-based modeling of the propagation of ultrashort focused pulses in nonlinear media
Por:
Reyes-Mora, Francisco J., Rodriguez-Herrera, Oscar G.
Publicada:
1 ene 2021
Resumen:
We present a method to calculate the spatio-temporal electric field
distribution of ultrashort focused pulses propagating in a nonlinear
medium with no absorption. The method combines the angular spectrum
technique, for propagating light beams, with the irradiance-dependent
refractive index of the medium. We modeled the propagation of ultrashort
mildly focused pulses, with different durations and peak powers, inside
a Ti:sapphire crystal characterized by its linear and nonlinear
refractive indices. Our method is able to reproduce the self-focusing
effect expected for nonlinear materials for incident beams with powers
above the critical power. We analyze the dependence of the focal length
and spot size within the nonlinear medium on the incident power and
compare them with the focal length and spot size for the same focusing
lens in free space. We also analyze the spot size and pulse duration as
a function of the distance traveled in the nonlinear medium for several
incident powers. Finally, we analyze the effect of the nonlinear medium
refractive index on the spatio-temporal distributions of the focused
pulse.
Filiaciones:
Reyes-Mora, Francisco J.:
Univ Nacl Autonoma Mexico, Inst Ciencias Aplicadas & Tecnol, Circuito Exterior S-N,Ciudad Univ, Mexico City 04510, DF, Mexico
Rodriguez-Herrera, Oscar G.:
Univ Nacl Autonoma Mexico, Inst Ciencias Aplicadas & Tecnol, Circuito Exterior S-N,Ciudad Univ, Mexico City 04510, DF, Mexico
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