Conventional surface plasmons have a wave vector exceeding that of light in vacuum, and therefore cannot be directly excited by is simply incident on the surface. However, we propose plasmon-polariton state can formed at boundary between metal dielectric Bragg mirror zero in-plane produced direct optical excitation. In analogy with electronic states crystal proposed Tamm, call these excitations Tamm plasmons, predict they may exist both TE TM polarizations are characterized parabolic...

We report on the first experimental observation of Tamm plasmon polaritons (TPPs) formed at interface between a metal and dielectric Bragg reflector (DBR). In contrast to conventional surface plasmons, TPPs have an in-plane wavevector less than light in vacuum, which allows for their direct optical excitation. The angular resolved reflectivity transmission spectra GaAs∕AlAs DBR covered by Au films various thicknesses show resonances associated with TPP low temperatures room temperature....

Abstract High carrier concentrations and the fluctuations in random potential resulting from ionized impurities alter density of states electron wavefunctions heavily doped semiconductors. The theoretical experimental work on these effects is reviewed, special attention being paid to consequences for optical transport properties. Semiconductor devices are often influence heavy doping illustrated injection laser bipolar transistor, which also serve as investigative tools.

We report on the Au-free molecular beam epitaxy growth of coherent GaAs nanowires directly Si(111) substrates. The is catalyzed by liquid Ga droplets formed in openings a native oxide layer at initial stage. Transmission electron microscopy studies demonstrate that are single crystals having zincblende structure along their length (apart from thin wurtzite region below droplet), regardless diameter (70--80 nm) and temperature range $(560--630\text{...

We show that logical signals encoded in bistable states semiconductor microcavities can be generated and controlled electronically by exploiting the electrical sensitivity of Tamm-plasmon--exciton-polariton modes. The transported along polariton neurons, created with a patterned metal surface. Using Gross-Pitaevskii equations, we simulate an electrically transistor find high repetition rates (10 GHz) are possible.

A series of calculations have been performed on group-III nitrides (GaN, AlN and InN) in both zinc-blende wurtzite structures. Three different levels computation an integrated programme study: first-principles total energy calculations, semi-empirical pseudopotential calculations. Bandstructures are obtained from each method a consistent manner, used to provide effective masses parameters for planned work the electronic structure alloys quantum well heterostructures.

Channeling of exciton polaritons in the plane semiconductor microcavities can be achieved by deposition metallic mesas on top structure. We show theoretically that regime strong coupling between cavity and Tamm surface plasmons is possible such structures. The effect favorable for spatial confinement formation hybrid one-dimensional plasmon-polariton modes.

We show that planar semiconductor microcavities in the strong coupling regime can be used as sources of stimulated terahertz radiation. Emitted photons would have a frequency equal to splitting cavity polariton modes. The optical transition between upper and lower branches is allowed due mixing state with one excited exciton states laser regime.

An electron in a random array of dense, weak scatterers is presented as model which expected to exhibit the typical features disordered system. average Green function for defined and derived Feynman path integral. In this formulation there clear similarity problem that nonmarkovian chain used further understanding problem. A selfconsistent method solving integral proposed then elucidate nature localized electronic states Particular attention paid at mobility edge spatial extent wavefunction...

The nature of the band gap in semiconducting material $\ensuremath{\beta}\ensuremath{-}{\mathrm{FeSi}}_{2}$ is still under some dispute. Although most experimental results indicate to be direct, ab initio work generally reports an indirect semiconductor with direct transition a few tens millielectron volts higher than gap. However, commonly grown epitaxially on diamond-structure Si substrate, and as consequence, unit cell strained. Here we report density-functional calculations, which have...

The authors present a theoretical study of band gap narrowing due to many-body effects in silicon and gallium arsenide at zero temperature. A principal aim the paper is give detailed description self-energy approach problem use plasmon pole approximation for dielectric response formalism. particular problems arising from multiple anisotropic bands, direct indirect gaps are considered. Numerical results presented electrons, holes an electron-hole plasma both Si GaAs. For case electrons where...

The design, measurement, and analysis of a range artificial materials for use at terahertz frequencies are described. chosen structures consist arrays cylindrical gold-plated pillars with period comparable to the wavelength incident radiation. An ultraviolet (UV) micromachining approach fabrication these high aspect-ratio is described using negative epoxy-based resin SU8. Lattice fence also realized same method. Terahertz (THz) frequency time domain spectroscopy performed on in 200 GHz 3.0...

We demonstrate theoretically that surface-plasmon polaritons, a form of optical Tamm state, can occur at the interface between metal and Bragg reflector frequencies above bulk plasma frequency metal. The excitations are within photonic band gap which provides required evanescent decay on side interface. At finite in-plane wave vector, low value permittivity its lead to an imaginary normal vector component in metal, localization other It is proposed necessary conditions be realized using...

Abstract A transfer matrix method is developed to calculate the electromagnetic field in a dielectric structure with circular cylindrical symmetry. The equations for reflection and transmission coefficients of waves from single boundary between two dielectrics multilayered are obtained. For interface, enhanced at small interface radii analogue Brewster effect predicted investigated. design an optimized Bragg reflector (CBR) proposed its optical properties studied. It found that thicknesses...

We observe hybrid states of cavity photons and Tamm plasmons in an organic microcavity with incorporated thin silver layer increasing thickness up to 40 nm. Via μ-photoluminescence spectroscopy, we investigate their angular dependence. At oblique angles, a TE-TM polarization splitting more than meV for each mode. An analytical model is developed describe the coupling account orthogonally polarized resonances.

We report measurements of the diffraction pattern a two-dimensional photonic quasicrystal structure and use set plane waves defined by as basis theoretical approach to calculate band system. An important feature model is that it retains essence rotational inflational properties at all levels approximation: lost in approximate models which artificially introduce elements periodicity.

Electronic band structure calculations have been performed for the wurtzite structures of AlN, GaN, and InN. In particular, conventional $\mathbf{k}\ensuremath{\cdot}\mathbf{p}$ valence parameters ${A}_{i} (i=1--7)$ computed from initial empirical pseudopotential in two distinct ways. A Monte Carlo fitting to data was used produce one set. Another set obtained directly formulas ${A}_{i}$ terms momentum matrix elements energy eigenvalues at center Brillouin zone. Both methods calculating...

Intervalence band absorption (IVBA) has been proposed as a possible cause of the temperature sensitivity threshold currents in longer-wavelength semiconductor lasers used for optical fibre communications. In view potential importance this effect, IVBA coefficients spin split off-heavy hole transition have evaluated GaAs, Ga0.47In0.53As and Ga0.28In0.72As0.6P0.4 temperatures range 150<T<400K concentrations from 0.75-3*1018 cm-3. The model incorporates structure momentum matrix elements based...

We report the measurements of diffraction pattern a two-dimensional Penrose-tiled photonic quasicrystal, obtained by etching air cylinders in silica substrate, and modelling light propagation dispersion relations photons inside such structure. The calculated transmission spectra exhibit dips whose positions are insensitive to direction depth increases with increasing structure length. An approach is developed for calculation which based on set reciprocal vectors defined pattern. curves...

Strong coupling of the whispering gallery modes with bulk excitons in semiconductor cylinders is demonstrated theoretically. The strong-coupling threshold governed by radiative decay rate optical modes, which we analyze as a function radius cylinder. Interestingly, value Rabi splitting found to be almost independent cylinder large limit. This consequence strong confinement modes.

The authors consider the problem of Auger recombination electrons and holes in quantum well heterostructure. An expression for rate is derived a particular process which equivalent so-called CCCH with carriers involved remaining lowest electron hole sub-bands. recombining are assumed to obey Boltzmann statistics. This restricted calculation regarded as useful preliminary study complete range processes well, use Fermi-Dirac

Abstract The frequency-dependent differential capacitance of an amorphous silicon Schottky barrier is calculated as a function d.c. bias using simple model the and assumed form for density electronic states, n(E), silicon. results show that at frequencies low 1 Hz can be considerably different from static because slow response electron occupancy localized states. A detailed development theory presented to demonstrate way in which information on n(E) contained within capacitance-voltage (CV)...