References of "Applied Physics A : Materials Science & Processing"
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See detailGrain boundaries in Cu (In, Ga) (Se, S)2 thin-film solar cells
Rau, Uwe; Taretto, Kurt; Siebentritt, Susanne UL

in Applied Physics A : Materials Science & Processing (2009), 96(1), 221-234

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See detailGaN and InN nanowires grown by MBE: A comparison
Calarco, Raffaella; Marso, Michel UL

in Applied Physics A : Materials Science & Processing (2007)

Morphological, optical and transport properties of GaN and InN nanowires grown by molecular beam epitaxy (MBE) have been studied. The differences between the two materials in respect to growth parameters ... [more ▼]

Morphological, optical and transport properties of GaN and InN nanowires grown by molecular beam epitaxy (MBE) have been studied. The differences between the two materials in respect to growth parameters and optimization procedure was stressed. The nanowires crystalline quality has been investigated by means of their optical properties. A comparison of the transport characteristics was given. For each material a band schema was shown, which takes into account transport and optical features and is based on Fermi level pinning at the surface. [less ▲]

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See detailNew approaches for growth control of GaN-based HEMT structure
Hardtdegen, H.; Steins, R.; Kaluza, N. et al

in Applied Physics A : Materials Science & Processing (2007), 87(3), 491-498

This paper reports on new approaches for growth control of GaN-based heterostructures for high frequency and high power application. First in situ methods are presented and their further development ... [more ▼]

This paper reports on new approaches for growth control of GaN-based heterostructures for high frequency and high power application. First in situ methods are presented and their further development discussed [1]. The development leads to a greatly improved observation of growth parameter influences in the MOVPE of GaN. A new growth process is introduced which enhances growth reproducibility [2]. This new growth process is then optimized with respect to the envisaged application. To this end process modeling will be employed. The application envisaged is the AlxGa1−xN/GaNhigh electron mobility transistor (HEMT). At last device results will be presented. All in all it will be shown how fundamental research can drive technology and how basic knowledge can be employed forprocess development with respect to device applications. [less ▲]

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See detailPerformance optimization of GaAs-based photomixers as sources of THz radiation
Kordoš, P.; Marso, Michel UL; Mikulics, M.

in Applied Physics A : Materials Science & Processing (2007), 87(3), 563-567

The performance optimization of GaAs-based photomixers using novel device structures is reported. Lowtemperature grown (LT) GaAs devices with recessed interdigitated finger contacts, which improve the ... [more ▼]

The performance optimization of GaAs-based photomixers using novel device structures is reported. Lowtemperature grown (LT) GaAs devices with recessed interdigitated finger contacts, which improve the electric field distribution in the active region, were investigated. Further, the devices with an enhancedmixing area using finger contacts integrated into the coplanar stripline were experimentally verified. The output power of such photomixers was twice of that with conventional surface contacts. High-energy nitrogen implanted GaAs was used as an alternative to LT GaAs, and a further increase of the output power was observed.Measured power level of 2.6 μW at 850 GHz was higher than that reported before for any photomixer in the THz region. [less ▲]

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See detailOptical absorption and electron energy loss spectra of carbon and boron nitride nanotubes: a first-principles approach
Marinopoulos, A. G.; Wirtz, Ludger UL; Marini, A. et al

in Applied Physics A : Materials Science & Processing (2004), 78(8), 1157-1167

We present results for the optical absorption spectra of small-diameter single-walled carbon and boron nitride nanotubes obtained by ab initio calculations in the framework of time-dependent density ... [more ▼]

We present results for the optical absorption spectra of small-diameter single-walled carbon and boron nitride nanotubes obtained by ab initio calculations in the framework of time-dependent density-functional theory. We compare the results with those obtained for the corresponding layered structures, i.e. the graphene and hexagonal boron nitride sheets. In particular, we focus on the role of depolarization effects, anisotropies, and interactions in the excited states. We show that the random phase approximation reproduces well the main features of the spectra when crystal local field effects are correctly included, and discuss to what extent the calculations can be further simplified by extrapolating results obtained for the layered systems to results expected for the tubes. The present results are relevant for the interpretation of data obtained by recent experimental tools for nanotube characterization, such as optical and fluorescence spectroscopies, as well as polarized resonant Raman scattering spectroscopy. We also address electron energy loss spectra in the small-q momentum-transfer limit. In this case, the interlayer and intertube interactions play an enhanced role with respect to optical spectroscopy. [less ▲]

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