Insulator-to-metal phase transition (PT) was produced by femtosecond light radiation in $\mathrm{V}{\mathrm{O}}_{2}$ thin films deposited on substrates with different thermal conductivities. Optical pump-probe techniques were applied to study the PT dynamics a ${10}^{\ensuremath{-}11}--{10}^{\ensuremath{-}9}\phantom{\rule{0.3em}{0ex}}\mathrm{s}$ time scale. Transient grating measurements conducted at laser pump fluences indicate that contribution insulator-to-metal subnanosecond scale effect...

This paper reports the first spectroscopic demonstration of photoluminescence (PL) owing to plasmon resonance energy transfer (PRET) from silver nanoparticles (NPs) luminescent species in glass. Optical absorption and PL spectroscopy experiments performed on melt-quenched silver-doped glass indicate presence single Ag+ ions, Ag+–Ag+ Ag+–Ag0 pairs, Ag NPs. After thermal processing material, nonradiative centers NPs is observed by uniform suppression band emission vanishing excitation...

A light-induced insulator-to-metal ultrafast phase transition (PT) was observed in $\mathrm{V}{\mathrm{O}}_{2}$ thin films deposited on single-crystal sapphire and amorphous glass substrates. The PT optical properties of were characterized by transient reflection, absorption, grating nonlinear measurements. crystalline substrates are spatially ordered show noticeable anisotropy response upon PT. Structural dependent the shear plane substrate. Significant twinning found for a...

Abstract Picosecond strain pulses are a versatile tool for investigation of mechanical properties meso- and nano-scale objects with high temporal spatial resolutions. Generation such is traditionally realized via ultrafast laser excitation light-to-strain transducer involving thermoelastic, deformation potential, or inverse piezoelectric effects. These approaches unavoidably lead to heat dissipation temperature rise, which can modify delicate specimens, like biological tissues, ultimately...

The light-induced insulator-to-metal phase transition was investigated by femtosecond pump-probe techniques in nanocrystalline ${\text{VO}}_{2}$ films. size of nanoparticles and the film morphology were found to be critical for ultrafast phase-transition dynamics. Experimental measurements third-order nonlinear susceptibility ${\ensuremath{\chi}}^{(3)}$ insulating at different excitation levels transient grating experiments show a size-dependent threshold behavior which is related process....

The degenerate-four-wave-mixing, ultrafast optical pump-probe reflection, and scattering techniques were applied to study the nonlinear properties of VO2 in insulating metallic phases. third-order susceptibility was measured for thin films at different excitation regimes. recovery dynamics after light-induced phase transition (PT) shows strong sensitivity pump energy could be governed by pure electronic relaxation excluding thermal contribution sufficiently low excitation. Increased light...

The femtosecond pump-probe technique was used to study the carrier dynamics of amorphous Ge2Sb2Te5 films. With density at around 1020−1021 cm−3, carriers were excited within 1 ps and recovered initial state for less than 3 ns. On picosecond time scale, relaxation consists two components: a fast process 5 slow after ps. component is function density, which increases from 1.9 4.3 changing 9.7×1020 cm−3 3.1×1021 cm−3. A possible interpretation processes elucidated. In first dominated by an...

The ultrafast elastic light scattering technique is applied to reveal the strong nonlinearity of V_{3}O_{5} associated with a photoinduced insulator-metal phase transition. Observation time-domain relaxation dynamics suggests several stages structural We discuss nonequilibrium processes in terms melting polaronic Wigner crystal, coalescence V-O octahedra, and photogeneration acoustical phonons low-T high-T phases V_{3}O_{5}. A molecular computation supports experimentally observed dynamics.

Distinct contribution of acoustic and optical phonons in light-induced lattice transformation was resolved at different time scales by monitoring the insulator-to-metal phase transition epitaxial nonepitaxial ${\mathrm{VO}}_{2}$ films. Applying ultrafast angle-resolved light scattering technique we demonstrate a significant influence internal misfit strain films on subpicosecond dynamics. This also allows for observing structural defects evolution transient state. The dynamics is discussed...

Measurements of ultrafast light scattering within a hemisphere are performed for statistical analysis nonequilibrium processes in VO2 epitaxial film. A Gerchberg-Saxton error reduction algorithm is applied accurate calculation surface autocorrelation function from data and partial reconstruction power spectral density function. Upon photoinduced phase transition VO2, the elastic reveals anisotropic grain-size-dependent dynamics. It was found that rate depends on optical absorption...

Angle-resolved reflection, light scattering and ultrafast pump-probe spectroscopy combined with a surface plasmon-polariton (SPP) resonance technique in attenuated total reflection geometry was used to investigate the light-induced plasmonic switching photorefractive VO2/Au hybrid structure. Measurements of SPP shows that optically-induced formation metallic state vanadium dioxide layer deposited on gold film significantly alters electromagnetic field enhancement propagation length at...

Ultrafast hemispherical angle-resolved light scattering technique is applied to monitor the insulator-to-metal phase transition of highly oriented VO2 crystalline films, where induced by femtosecond laser pulses. This approach reveals principal differences in transient dynamics multi-scale grains for thermally and light-induced transformation, showing anisotropic grain-size-dependent behavior with high resolution space time. Complete photoinduced occurs within 500 fs. However, different...

The compound V3O5, a member of the vanadium oxide Magnéli series, exhibits metal-insulator transition near 430 K, highest known temperature value among all oxides. It has been studied before mainly in single-crystal form, and for very few cases which thin films have fabricated before, procedure required extensive post-deposition annealing other oxides or metal at high temperatures tightly controlled atmospheres. For present work, V3O5 were deposited directly on SiO2 glass substrates, without...

Vanadium sesquioxide (V2O3) exhibits remarkable property changes through its metal-insulator transition near 150 K and is a very promising candidate for device applications. Thin V2O3 films were deposited on SiO2 glass by reactive DC magnetron sputtering. While resistivity over four orders of magnitude demonstrated, under nominally identical conditions exhibited significant differences in electrical characteristics, which would hinder reproducibility deposition techniques appropriate...