Zobrazeno 1 - 10
of 39
pro vyhledávání: '"K Wilmers"'
Autor:
M. Keim, G. Landwehr, K. Wilmers, Wolfgang Richter, Norbert Esser, J. Geurts, Andrzej Fleszar, G. Reuscher, Veit Wagner, Andreas Waag
Publikováno v:
Journal of Crystal Growth. :340-344
Beryllium chalcogenides are a new class of II–VI materials and promising candidates for UV/VIS applications. In this paper we analyse the optical properties of the quaternary BeMgZnSe system lattice matched to GaAs. We investigate the compositional
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::b156b3bf863b922a4b42ec5211ad42db
https://doi.org/10.1016/s0022-0248(00)00104-4
https://doi.org/10.1016/s0022-0248(00)00104-4
Autor:
N. V. Edwards, Robert F. Davis, T. Wethkamp, Irina Buyanova, K. Wilmers, David E. Aspnes, S. D. Yoo, Norbert Esser, C. Cobet, Bo Monemar, A. D. Batchelor, Lynnette D. Madsen, Michael D. Bremser
Publikováno v:
Thin Solid Films. 364:98-106
Our work primarily concerns the characterization of wide-gap III-V nitride semiconductors, nondestructively and at variable temperature, with spectroscopic ellipsometry (SE) and reflectometry in the spectral range from 1.5 to 6 eV. In the case of GaN
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::b8354da8af7f68e4872e410a33070feb
https://doi.org/10.1016/s0040-6090(99)00903-7
https://doi.org/10.1016/s0040-6090(99)00903-7
Autor:
Manuel Cardona, Lorin X. Benedict, T. Wethkamp, C. Cobet, Wolfgang Richter, K. Wilmers, Eric L. Shirley, Norbert Esser
Publikováno v:
Solid State Communications. 112:129-133
Measurements and calculations of the dielectric function of wurtzite GaN and AlN are presented. Spectroscopic ellipsometry was used to determine ϵ ( ω ) of thin film samples in the energy range from 3 to 9.8 eV. Calculations of ϵ ( ω ) for the bu
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::c255eee9eb20be91e83b9433ea7f884b
https://doi.org/10.1016/s0038-1098(99)00323-3
https://doi.org/10.1016/s0038-1098(99)00323-3
Autor:
M. Cardona, Andreas Waag, F. Fischer, M. Keim, Veit Wagner, Wolfgang Richter, C. Cobet, H.-J. Lugauer, Norbert Esser, T. Gerhard, T. Wethkamp, K. Wilmers
Publikováno v:
Scopus-Elsevier
We have determined the dielectric function (DF) of beryllium chalcogenides between 2.5 and 25 eV using an ellipsometer operating with synchrotron radiation in the VUV range. The VUV ellipsometer is, in particular, useful for the characterization of w
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4f0593dfc30b294ea6a3cb9def664b7e
https://doi.org/10.1002/(sici)1521-3951(199909)215:1<15::aid-pssb15>3.0.co
https://doi.org/10.1002/(sici)1521-3951(199909)215:1<15::aid-pssb15>3.0.co
Autor:
Veit Wagner, M. Keim, F. Fischer, W. Richter, H.-J. Lugauer, T. Gerhard, Norbert Esser, T. Wethkamp, K. Wilmers, C. Cobet, Manuel Cardona
Publikováno v:
Journal of Electronic Materials. 28:670-677
We have determined the dielectric function of BeTe and BexZn1−xSe for the full composition range (0≤x≤1) by spectroscopic ellipsometry in the ultraviolet- and vacuum ultraviolet-range. The spectra show pronounced features in the photon energy r
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::ab9d5bc57af7af7bc1bfc0d2dec2f9dd
https://doi.org/10.1007/s11664-999-0052-8
https://doi.org/10.1007/s11664-999-0052-8
Autor:
T. Wethkamp, Wolfgang Richter, C. Cobet, H.-J. Lugauer, M. Keim, Veit Wagner, Norbert Esser, T. Gerhard, Manuel Cardona, F. Fischer, K. Wilmers
Publikováno v:
Physical Review B. 59:10071-10075
We have determined the dielectric function of ${\mathrm{Be}}_{x}{\mathrm{Zn}}_{1\ensuremath{-}x}\mathrm{Se}$ above the fundamental absorption edge for the full composition range $(0l~xl~1)$ by spectroscopic ellipsometry in the UV and VUV range. The s
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9a4ee3b85c69b8e3fc3429fb44bd98ef
https://doi.org/10.1103/physrevb.59.10071
https://doi.org/10.1103/physrevb.59.10071
Autor:
T. Wethkamp, M. Cardona, Oliver Ambacher, H. Angerer, Norbert Esser, Robert L. Johnson, G. Jungk, W. Richter, K. Wilmers
Publikováno v:
Thin Solid Films. :745-750
The dielectric functions of the wide-bandgap semiconductors GaN and Al x Ga 1− x N (hexagonal phase on c-sapphire) are determined directly for the first time in the spectral range 3–25 eV using an ellipsometry set-up operating with synchrotron ra
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::7886ea6700c32f935dcf4fb7019b5a20
https://doi.org/10.1016/s0040-6090(97)00990-5
https://doi.org/10.1016/s0040-6090(97)00990-5
Publikováno v:
Environmental Health Perspectives
In the State Laboratory of North Rhine-Westphalia for Food, Pharmaceutical and Environmental Chemistry (Chemisches Landesuntersuchungsamt), more than 600 individual human milk samples have been analyzed for polychlorinated dibenzo-p-dioxins (PCDDs) a
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4a82207d3406866e0a9ce2fc6b6abbd5
http://europepmc.org/articles/PMC1566908
http://europepmc.org/articles/PMC1566908
Publikováno v:
Chemosphere. 27:1349-1357
Three surveys were conducted to better know the factors which influence the PCDD/PCDF levels in cow's milk. These investigations comprised analyses of cow's milk, soil and grass at different sampling sites. The results show that the contamination lev
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9e343d215f0516b999b42023796c8614
https://doi.org/10.1016/0045-6535(93)90229-x
https://doi.org/10.1016/0045-6535(93)90229-x
Publikováno v:
Chemosphere. 25:1029-1038
Since 1984 more than 600 human milk samples have been analyzed in our institute for PCDDs, PCDFs, PCBs and organochlorine pesticides (OCPs). All samples were collected on a voluntary basis from nursing mothers mostly living in North Rhine-Westphalia
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::72617b78430b1bdb64b2d93f717deb0f
https://doi.org/10.1016/0045-6535(92)90103-x
https://doi.org/10.1016/0045-6535(92)90103-x