Two-photon resonant picosecond pulse propagation in lithium vapor

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:5107969

Mukherjee, A

The anomalous transmission of 90 phase shifted pulse pair through a TPR medium (2s-4s transition in lithium) has been experimentally demonstrated. It was seen that the dynamic Stark shift (being proportional to the intensity) played a crucial role in the tuning of a short pulse in two photon resonant interaction. Over a scan of about typically 0.2 nm in the average wavelength of the pulse, the resonance (stark tuned) could be swept from the peak field (maximum Stark shift) to zero field (zero Stark shift). Thus over only a little portion (temporal) of the pulse can the resonance condition be fulfilled, where the intensity of the field generates just enough Stark shift to compensate the detuning from zero field resonance. It has been proved that the coherence of multiphoton excitation can be studied by appropriately phased and time delayed sequence of pulses. An application of this fundamental study of coherence has been made for the enhancement of third harmonic generation. The coherent recovery of the energy lost to the two photon absorption process enabled the total interaction to be longer (than an incoherent interaction or coherent, but not 90 phase shifted pulse pair) and by proper phase matching gave an enhancement of third harmonic generation.

• Research Organization: North Texas State Univ., Denton, TX (USA)
• OSTI ID: 5107969
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
426002* -- Engineering-- Lasers & Masers-- (1990-)
DATA
EXPERIMENTAL DATA
GAS LASERS
HARMONICS
INFORMATION
LASERS
METAL VAPOR LASERS
NUMERICAL DATA
OSCILLATIONS
RESONANCE
STARK EFFECT
TRANSMISSION
TUNING
WAVE PROPAGATION