Modulation of supercontinuum generation and formation of an attosecond pulse from a generalized two-level medium
2007 (English)In: Journal of Physics B: Atomic, Molecular and Optical Physics, ISSN 0953-4075, E-ISSN 1361-6455, Vol. 40, 1523-1534 p.Article in journal (Refereed) Published
The propagation of ultrashort pulses in a generalized two- level system, consisting of permanent dipole moments, is simulated by solving the full Maxwell - Bloch equations. Special attention has been paid to the supercontinuum generation of spectra and the formation of attosecond ( as) pulses. It is found that the supercontinuum generation is strongly modulated by both area and width of the pulse, resulting from the interference between the splitting pulses in the time domain and the implication of the time - energy uncertainty relation. The effect of the permanent dipole moment on the supercontinuum generation is discussed in detail. Calculations show that a well- shaped 132 as pulse can be generated from a 2 fs incoming pulse under the condition where the permanent dipole moment difference between two levels is equal to the transition dipole moment between them. Influences of carrier- envelope phase and time- dependent ionization on the spectral and temporal evolution of the ultrashort pulses are also discussed at length.
Place, publisher, year, edition, pages
2007. Vol. 40, 1523-1534 p.
femtosecond optical pulses, laser-pulses, ionization
IdentifiersURN: urn:nbn:se:kth:diva-11458DOI: 10.1088/0953-4075/40/8/006ISI: 000246010300007ScopusID: 2-s2.0-34247138000OAI: oai:DiVA.org:kth-11458DiVA: diva2:276739
QC 201006302009-11-112009-11-112010-11-22Bibliographically approved