Rovibrational Wave-Packet Dispersion during Femtosecond Laser Filamentation in Air

Journal Article · Fri Aug 14 04:00:00 EDT 2009 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.103.075005· OSTI ID:21370664

Odhner, J H; Romanov, D A; Levis, R J ^[1]

---

1. Department of Chemistry and Center for Advanced Photonics Research, Temple University, Philadelphia, Pennsylvania 19122 (United States)

An impulsive, femtosecond filament-based Raman technique producing high quality Raman spectra over a broad spectral range (1554.7-4155 cm{sup -1}) is presented. The temperature of gas phase molecules can be measured by temporally resolving the dispersion of impulsively excited vibrational wave packets. Application to laser-induced filamentation in air reveals that the initial rovibrational temperature is 300 K for both N{sub 2} and O{sub 2}. The temperature-dependent wave-packet dynamics are interpreted using an analytic anharmonic oscillator model. The wave packets reveal a 1/e dispersion time of 3.9 ps for N{sub 2} and 2.8 ps for O{sub 2}. Pulse self-compression of temporal features to 8 fs within the filament is directly measured by impulsive vibrational excitation of H{sub 2}.

• OSTI ID: 21370664
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 7 Vol. 103; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
AIR
ANHARMONIC OSCILLATORS
DISPERSIONS
ELEMENTS
ENERGY-LEVEL TRANSITIONS
EXCITATION
FILAMENTS
FLUIDS
GASES
HYDROGEN
LASERS
NONMETALS
PULSES
RAMAN SPECTRA
SPECTRA
TEMPERATURE DEPENDENCE
WAVE PACKETS