Efficient continuous-wave (cw) lasing of Cr(2+):ZnS and Cr(2+):ZnSe crystals in external hemispherical cavities and in a microchip configuration under Er-fiber-laser pumping at room temperature are reported. The key result is what is believed to be the first successful demonstration of cw Cr(2+):ZnS and Cr(2+):ZnSe microchip lasers with maximum output powers of 63 and 100 mW at 2320 and 2520 nm...

Address correspondence to [email protected] ABSTRACT We report synthesis windows for growth of millimeter-long ZnTe nanoribbons and ZnSe nanowires using vapor transport. By tuning the local conditions at the growth substrate, high aspect ratio nanostructures can be synthesized. A Cu-ion immersion doping method was applied, producing strongly p-type conduction in ZnTe and ionic conduction in ZnSe...

The changes of structural and photoluminescence (PL) characteristics of MBE-grown CdZnSe/ZnSe single quantum well (QW) structures caused by Cd/Zn interdiffusion were studied by high-resolution X-ray diffraction (HRXRD) and low-temperature PL methods. The PL investigations showed that the increase of Cd content in the QW resulted in the increase of the depth of potential fluctuations in the QW a...

The distribution of dislocations and domains found in thin ZnSe films grown by molecular-beam epitaxy on GaAs(100) has been examined with low-temperature cathodoluminescence (CL) imaging and spectroscopy. Dark-line and bright-line defects in the low-temperature CL imaging of the free-exciton (FE) and Y-band emissions, respectively, are found to correlate with the presence of [ 1 iO]-oriented mi...

First-principles total-energy calculations reveal a novel local atomic reconstruction mode around anion vacancies in II-VI and chalcopyrite compounds resulting from the formation of metal dimers. As a consequence, the neutral Se vacancy has an unexpected low symmetry in ZnSe and becomes a deep donor in both ZnSe and CuGaSe2, contrary to the common belief regarding chalcopyrites. The calculated ...

Colloidal cadmium selenide (CdSe) and zinc selenide (ZnSe) quantum dots with a hexagonal structure were synthesized by irradiating an aqueous solution containing metal precursors, poly (vinyl pyrrolidone), isopropyl alcohol, and organic solvents with 1.25-MeV gamma rays at a dose of 120 kGy. The radiolytic processes occurring in water result in the nucleation of particles, which leads to the gr...

In this study we introduce a new method for the one-pot synthesis of core/shell/shell alloyed Cd1-xZnxSe/ZnSe/ZnS QDs and examine the effect of the shell coating on the optical properties and exciton dynamics of the alloy core. The photoluminescence (PL) quantum yield is greatly enhanced after shell growth, from 9.6% to 63%. The exciton dynamics were studied by time correlated single photon cou...

We report on a comprehensive study of the ZnSe(100)-c(232)-Na interface using x-ray and UV photoemission, and x-ray-induced Auger spectroscopy. Spectra were taken after stepwise Na deposition onto a clean c(232)-reconstructed ZnSe~100! surface at room temperature up to a saturation coverage of about 1 ML of Na and after annealing. Based on the analysis of Auger parameters and of the relative in...

Hybrid semiconductor (SC)/ ferromagnetic (FM) structures have been investigated due to the possibility of using not only the charge but also the spin of electrons to conceive new electronic devices [1-3]. In particular, ZnSe has been pointed out as one attracting candidate to achieve such goal due to their favorable chemical stability in the presence of Fe [4] and theoretical calculations sugge...

Nonlinear Optical Spectroscopy of Solid/Solid Interfaces Mohsen S. Yeganeh Arjun G. Yodh Three-wave mixing (3WM) spectroscopy is an exciting and relatively unexplored probe of buried solid interfaces. It possesses long penetration depths characteristic of most optical methods and intrinsic interface specificity characteristic of second-order optical processes. In this thesis we present frequenc...