The possibility of obtaining a high specific input energy in an electron-beam sustained discharge ignited in oxygen gas mixtures O 2 : Ar : CO (or H 2) at the total gas pressures of 10-100 Torr was experimentally demonstrated. The specific input energy per molecular component exceeded ∼6 kJ l −1 atm −1 (150 kJ mol −1) as a small amount of carbon monoxide was added into a gas mixture of oxygen and argon. It was theoretically demonstrated that one might expect to obtain a singlet delta oxygen yield of 25% exceeding its threshold value needed for an oxygen-iodine laser operation at room temperature, when maintaining a non-self-sustained discharge in oxygen gas mixtures with molecular additives CO, H 2 or D 2. The efficiency of singlet delta oxygen production can be as high as 40%.

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Transient stimulated Raman scattering (SRS) of 0.3 ps 515 nm laser pulses in B a W O 4 crystal was experimentally demonstrated with efficiency up to ∼ 20 % for the Stokes component with a wavenumber of ∼ 925 c m − 1 in a simple single-pass geometry. This anomalous high efficiency was obtained due to the laser pulse self-phase modulation resulting in spectral broadening and seeding the SRS. The applicability of seed pulse production for a high-pressure sub-picosecond C O 2 laser amplifier via difference frequency generation in L i G a S 2 crystal was numerically verified.

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Ultrafast intense photoexcitation of a silicon surface is complementarily studied experimentally and theoretically, with its prompt optical dielectric function obtained by means of time resolved optical reflection microscopy and the underlying electron-hole plasma dynamics modeled numerically, using a quantum kinetic approach. The corresponding transient surface plasmon-polariton (SPP) dispersion curves of the photo excited material were simulated as a function of the electron-hole plasma density, using the derived optical dielectric function model, and directly mapped at several laser photon energies, measuring spatial periods of the corresponding SPP mediated surface relief nanogratings. The unusual spectral dynam ics of the surface plasmon resonance, initially increasing with the increase in the electron-hole plasma den sity but damped at high interband absorption losses induced by the high density electron-hole plasma through instantaneous bandgap renormalization, was envisioned through the multi color mapping.