Ultrafast photoexcited carrier dynamics in CdS nanoparticles prepared by an AOT/n-heptane reversed micelle system were investigated by a femtosecond visible-pump/mid-IR probe technique. A mid-IR probe beam was found to mainly probe the ultrafast dynamics of photoexcited electrons in the conduction band. Dispersions of CdS nanoparticles with 8 different mean diameters from 2.9 to 4.1 nm were pre...

We discuss the dynamics of ultrashort pulsed laser excitation in bulk optical silica-based glasses (fused silica and borosilicate BK7) well-above the permanent modification threshold. We indicate subsequent structural and thermomechanical energy relaxation paths that translate into positive and negative refractive index changes, compression and rarefaction zones. If fast electronic decay occurs...

In order to combine advantages of ZnO thin film transistors (TFTs) with a high on-off ratio and graphene TFTs with extremely high carrier mobility, we present a facile methodology for fabricating ZnO thin film/graphene hybrid two-dimensional TFTs. Hybrid TFTs exhibited ambipolar behavior, an outstanding electron mobility of 329.7 ± 16.9 cm(2)/V·s, and a high on-off ratio of 10(5). The ambipolar...

Attosecond science has paved the way for direct probing of electron dynamics in gases and solids. This review provides an overview of recent attosecond measurements, focusing on the wealth of knowledge obtained by the application of isolated attosecond pulses in studying dynamics in gases and solid-state systems. Attosecond photoelectron and photoion measurements in atoms reveal strong-field tu...

Time-resolved photoluminescence measurements of carrier lifetimes in modulation-doped s100 Åd AlxGa1−xN/ s100 Åd GaN multiple quantum well heterostructures are reported. The photoluminescence sPLd spectrum exhibits several lines associated with recombination of carriers from multiple excited electron states to the hole ground state. The PL decay times associated with ground state recombination,...

Exciton-polaritons form upon strong coupling between electronic excitations of a material and photonic states of a surrounding microcavity. In organic semiconductors the special nature of excited states leads to particularly strong coupling and facilitates condensation of exciton-polaritons at room temperature, which may lead to electrically pumped organic polariton lasers. However, charge carr...

Ultrafast pump-probe and transient photoluminescence spectroscopy were used to investigate carrier dynamics in β-Ga2O3 nanowires converted to β-Ga2O3/Ga2S3 under H2S between 400 to 600 °C. The β-Ga2O3 nanowires exhibited broad blue emission with a lifetime of 2.4 ns which was strongly suppressed after processing at 500-600 °C giving rise to red emission centered at 680 nm with a lifetime of 19 ...

The Cu-based oxygen carrier is a promising material in the chemical looping with uncoupling (CLOU) process, while its performance CLOU significantly dependent on release properties. However, study of mechanisms not comprehensive enough. In this work, detailed CuO(110) and CuO(111) are researched at an atomic level using density functional theory (DFT) method, including formation O2, desorption ...

— Using a master-equation approach for the description of coherent and incoherent dynamics in ‘artificial atoms and molecules’, we present a theoretical analysis of situations where intense laser fields lead to pronounced renormalizations of carrier states. Such enhanced light-matter interactions allow for the solid-state implementation of effects hitherto only observable in atomic systems. Two...

Due to small, “sub-excitonic” dimensions, semiconductor nanocrystals can produce novel electronic interactions that involve charges residing in intrinsic quantized states as well as species located at nanocrystal surfaces. Strong interactions between quantum-confined carriers open, for example, a new nanocrystal-speci fic energy relaxation channel associated with Augertype electron-hole energy ...