Visualization of focusing–refocusing cycles during filamentation in BaF2

  title={Visualization of focusing–refocusing cycles during filamentation in BaF2},
  author={Aditya K. Dharmadhikari and Jayashree A. Dharmadhikari and Deepak Mathur},
  journal={Applied Physics B},
Filamentation occurs within a 1.5 cm-long crystal of BaF2 during the propagation of intense, ultrashort (40 fs) pulses of 800 nm light; a systematic study as a function of incident power enables us to extract quantitative information on laser intensity within the condensed medium, the electron density and the six-photon absorption cross section. At low incident power, a single filament is formed within the crystal; two or more filaments are observed along the direction transverse to laser… 
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