Effect of the shape of an approximate potential on the calculation of vibrational levels of diatomic molecules

The effect of the potential shape on the calculation of vibrational levels of diatomic molecules is investigated in terms of the molecular parameters, obtained from its Dunham, Ogilvie-Tipping, Simons-Parr-Finlan, and Takkar approximate expansions. It is established that the last two representations provide the best reconstruction of vibrational levels from an adjustable potential.     

A study of the compounds which are induced on the metallic target surface under the action of a pulsed laser plasmatron

The compounds induced on the surface of titanium and copper targets by a breakdown plasma produced by focused TEA-CO₂ high-repetition frequency laser pulses was studied by transmission electron microscopy and selected area diffraction in correlation with absorptivity data determined before and after laser irradiation. The possibility of using TEA-CO₂ lasers to produce complex thermal treatments was demonstrated for metallic surfaces by the modification of the physico-chemical properties at the sites of plasma action on these surfaces.     

Mode-locked 1.93 microm thulium fiber laser with a carbon nanotube absorber

We report a ring-cavity thulium fiber laser mode locked with a single-wall carbon nanotube absorber used in transmission. A carboxymethyl cellulose polymer film with incorporated carbon nanotubes synthesized by the arc discharge method has an absorption coinciding with in the amplification bandwidth of a Tm-doped fiber. This laser is pumped by an erbium fiber laser at 1.57 microm wavelength and produces a 37 MHz train of mode-locked 1.32 ps pulses at 1.93 microm wavelength with an average output power of 3.4 mW.     

Antireflection structures written by excimer laser on CVD diamond

Two-dimensional antireflective periodical microstructures for the IR range are fabricated on the surface of CVD diamond films. These structures are created using an ArF excimer laser (λ=193 nm) and a direct writing scheme consisting of a beam collimator and a microscope objective to focus the beam onto the sample. Two different arrays are investigated. One has a spacing of 3 μm and is produced with single shots and the other one has a spacing of 4 μm and is produced with three shots per spot. The hole depth and shape are measured with an atomic force microscope (AFM). The optical transmittance and the scattering properties of the structure at 10.6 μm are reported for a CO₂ laser beam. With a spectrometer further transmission measurements in the range of 5 to 20 μm are performed. Received: 16 September 1999 / Accepted: 11 October 1999 / Published online: 24 March 2000     

Laser transfer of diamond nanopowder induced by metal film blistering

Blister-based laser induced forward transfer (BB-LIFT) is a promising technique to produce surface microstructures of various advanced materials including inorganic and organic micro/nanopowders, suspensions and biological micro-objects embedded in life sustaining medium. The transferred material is spread over a thin metal film irradiated from the far side by single laser pulses through a transparent support. Interaction of the laser pulse with the metal–support interface under optimized conditions causes formation of a quickly expanding blister. Fast movement of the free metal surface provides efficient material transfer, which has been investigated for the case of diamond nanopowder and diamond-containing suspension. The unique features of the given technique are universality, simplicity and efficient isolation of the transferred material from the ablation products and laser heating.     

Periodic Orbits and Bifurcations of the Vibrational Modes of the Ozone Molecule at High Energies

Russian Physics Journal - The study of quantum states near the dissociation threshold is necessary both to understand the formation of molecules and to explore accurately chemical reactions....     

Gas-phase growth of silicon-doped luminescent diamond films and isolated nanocrystals

A method of controlled diamond doping, consisting in introducing a solid-state silicon source into a CVD reactor chamber is proposed and implemented. Such an approach is tested during diamond film and isolated nanocrystallite growth on silicon, molybdenum, sapphire, copper, and quartz substrates. The approach to nanodiamond doping with silicon during CVD synthesis, developed in this paper, is promising for developing stable highly efficient luminescent nanodiamonds.