Search Results - "Walukiewicz, W."

Engineering the electronic band structure for multiband solar cells by López, N, Reichertz, L A, Yu, K M, Campman, K, Walukiewicz, W

“…Using the unique features of the electronic band structure of GaN(x)As(1-x) alloys, we have designed, fabricated and tested a multiband photovoltaic device…”
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Intrinsic limitations to the doping of wide-gap semiconductors by Walukiewicz, W

“…Doping limits in semiconductors are discussed in terms of the amphoteric defect model (ADM). It is shown that the maximum free electron or hole concentration…”
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Controlling the Curie temperature in (Ga,Mn)As through location of the Fermi level within the impurity band by Dobrowolska, M., Tivakornsasithorn, K., Liu, X., Furdyna, J. K., Berciu, M., Yu, K. M., Walukiewicz, W.

“…The ferromagnetic semiconductor (Ga,Mn)As has emerged as the most studied material for prototype applications in semiconductor spintronics. Because…”
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Finite element simulations of compositionally graded InGaN solar cells by Brown, G.F., Ager, J.W., Walukiewicz, W., Wu, J.

“…The solar power conversion efficiency of compositionally graded In x Ga 1− x N solar cells was simulated using a finite element approach. Incorporating a…”
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Valence band anticrossing in GaBixAs1−x by Alberi, K., Dubon, O. D., Walukiewicz, W., Yu, K. M., Bertulis, K., Krotkus, A.

“…The optical properties of GaBixAs1−x(0.04<x<0.08) grown by molecular beam epitaxy have been studied by photomodulated reflectance spectroscopy. The alloys…”
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Indium doped Cd1-xZnxO alloys as wide window transparent conductors by Zhu, Wei, Yu, Kin Man, Walukiewicz, W.

“…We have synthesized Indium doped Cd1-xZnxO alloys across the full composition range using magnetron sputtering method. The crystallographic structure of these…”
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Unusual properties of the fundamental band gap of InN by Wu, J., Walukiewicz, W., Yu, K. M., Ager, J. W., Haller, E. E., Lu, Hai, Schaff, William J., Saito, Yoshiki, Nanishi, Yasushi

“…The optical properties of wurtzite-structured InN grown on sapphire substrates by molecular-beam epitaxy have been characterized by optical absorption,…”
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Small band gap bowing in In1−xGaxN alloys by Wu, J., Walukiewicz, W., Yu, K. M., Ager, J. W., Haller, E. E., Lu, Hai, Schaff, William J.

“…High-quality wurtzite-structured In-rich In1−xGaxN films (0⩽x⩽0.5) have been grown on sapphire substrates by molecular beam epitaxy. Their optical properties…”
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Electronic band structure of highly mismatched GaN1−xSbx alloys in a broad composition range by Segercrantz, N., Yu, K. M., Ting, M., Sarney, W. L., Svensson, S. P., Novikov, S. V., Foxon, C. T., Walukiewicz, W.

“…In this letter, we study the optical properties of GaN1−xSbx thin films. Films with an Sb fraction up to 42% were synthesized by alternating GaN-GaSb layers at…”
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Nature of room-temperature photoluminescence in ZnO by Shan, W., Walukiewicz, W., Ager, J. W., Yu, K. M., Yuan, H. B., Xin, H. P., Cantwell, G., Song, J. J.

“…The temperature dependence of the photoluminescence (PL) transitions associated with various excitons and their phonon replicas in high-purity bulk ZnO has…”
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Conduction band modifications by d states in vanadium doped CdO by Li, Y.J., Yu, K.M., Chen, G.B., Liu, Chao Ping, Walukiewicz, W.

“…3d transition metal ions have been shown to act as donors and to introduce highly localized d-levels when incorporated in CdO. In this work, we synthesized CdO…”
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Nitrogen-related intermediate band in P-rich GaNxPyAs1−x−y alloys by Zelazna, K., Gladysiewicz, M., Polak, M. P., Almosni, S., Létoublon, A., Cornet, C., Durand, O., Walukiewicz, W., Kudrawiec, R.

“…The electronic band structure of phosphorus-rich GaN x P y As 1−x−y alloys (x ~ 0.025 and y ≥ 0.6) is studied experimentally using optical absorption,…”
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Multicolor emission from intermediate band semiconductor ZnO1−xSex by Welna, M., Baranowski, M., Linhart, W. M., Kudrawiec, R., Yu, K. M., Mayer, M., Walukiewicz, W.

“…Photoluminescence and photomodulated reflectivity measurements of ZnOSe alloys are used to demonstrate a splitting of the valence band due to the band…”
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Electronic band structure of ZnO-rich highly mismatched ZnO1−xTex alloys by Ting, M., dos Reis, R., Jaquez, M., Dubon, O. D., Mao, S. S., Yu, K. M., Walukiewicz, W.

“…We synthesized ZnO1−xTex alloys with Te composition x < 0.23 by using pulsed laser deposition. Alloys with x < 0.06 are crystalline with a columnar growth…”
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Crystal structure and properties of CdxZn1−xO alloys across the full composition range by Detert, D. M., Lim, S. H. M., Tom, K., Luce, A. V., Anders, A., Dubon, O. D., Yu, K. M., Walukiewicz, W.

“…We have synthesized CdxZn1−xO alloys across the full composition range. The structural mismatch of the two endpoint compounds splits the alloy into two regions…”
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Effects of the d-donor level of vanadium on the properties of Zn1−xVxO films by García-Hemme, E., Yu, K. M., Wahnon, P., González-Díaz, G., Walukiewicz, W.

“…We report the effect of d-levels of vanadium atoms on the electronic band structure of ZnO. Polycrystalline layers of Zn1−xVxO with 0 ≤ x ≤ 0.08 were…”
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Photoreflectance studies of optical transitions in GaNPAs intermediate band solar cell absorbers by Zelazna, K., Kudrawiec, R., Luce, A., Yu, K.-M., Kuang (邝彦瑾), Y.J., Tu, C.W., Walukiewicz, W.

“…Photoreflectance spectroscopy is used to study optical properties of GaNPAs for the intermediate band (IB) solar cell absorbers. The IB is created in GaNPAs by…”
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Effects of electron concentration on the optical absorption edge of InN by Wu, J., Walukiewicz, W., Li, S. X., Armitage, R., Ho, J. C., Weber, E. R., Haller, E. E., Lu, Hai, Schaff, William J., Barcz, A., Jakiela, R.

“…InN films with free electron concentrations ranging from mid-1017 to mid-1020 cm−3 have been studied using optical absorption, Hall effect, and secondary ion…”
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Multiband GaNAsP quaternary alloys by Yu, K. M., Walukiewicz, W., Ager, J. W., Bour, D., Farshchi, R., Dubon, O. D., Li, S. X., Sharp, I. D., Haller, E. E.

“…We have synthesized GaN x As 1 − y P y alloys ( x ∼ 0.003 − 0.01 and y = 0 - 0.4 ) using nitrogen (N) ion implantation into GaAsP epilayers followed by pulsed…”
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InGaN pn-junctions grown by PA-MBE: Material characterization and fabrication of nanocolumn electroluminescent devices by Gherasoiu, I., Yu, K.M., Reichertz, L., Walukiewicz, W.

“…PN junctions are basic building blocks of many electronic devices and their performance depends on the structural properties of the component layers and on the…”
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