| Record 1 of 9 |
| Author(s): Song, XH (Song, Xiaohui); Jin, YR (Jin, Yirong); Zhang, X (Zhang, Xin); Yu, YD (Yu, Yude); Zhang, DL (Zhang, Dian-lin) |
| Title: A simple ac bridge for detecting small resistance change |
| Source: REVIEW OF SCIENTIFIC INSTRUMENTS, 80 (8): Art. No. 086104 AUG 2009 |
| Abstract: A simple ac resistance bridge is proposed. The stability of the design is better than 10(-6), which is especially suitable for detecting tiny changes of resistance. An example of magnetoresistance measurement for a 220 nm Au film shows the good performance of the bridge. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3202284] |
| ISSN: 0034-6748 |
| Article Number: 086104 |
| DOI: 10.1063/1.3202284 |
| Record 2 of 9 |
| Author(s): Li, F (Li, Feng); Jiao, HJ (Jiao, Hujun); Luo, JY (Luo, Juyan); Li, XQ (Li, Xin-Qi); Gurvitz, SA (Gurvitz, S. A.) |
| Title: Coulomb blockade double-dot Aharonov-Bohm interferometer: Giant fluctuations |
| Source: PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES, 41 (9): 1707-1711 SEP 2009 |
| Abstract: Electron transport through two parallel quantum dots is a kind of solid-state realization of double path interference We demonstrate that the inter-clot Coulomb correlation and quantum coherence would result in strong current fluctuations with a divergent Fano factor at zero frequency. We also provide physical interpretation for this surprising result, which displays its generic feature and allows us to recover this phenomenon in more complicated systems. (C) 2009 Elsevier B.V. All rights reserved. |
| ISSN: 1386-9477 |
| DOI: 10.1016/j.physe.2009.06.006 |
| Record 3 of 9 |
| Author(s): Zhang, ZZ (Zhang, Z. Z.); Wu, ZH (Wu, Z. H.); Chang, K (Chang, Kai); Peeters, FM (Peeters, F. M.) |
| Title: Resonant tunneling through S- and U-shaped graphene nanoribbons |
| Source: NANOTECHNOLOGY, 20 (41): Art. No. 415203 OCT 14 2009 |
| Abstract: We theoretically investigate resonant tunneling through S- and U-shaped nanostructured graphene nanoribbons. A rich structure of resonant tunneling peaks is found emanating from different quasi-bound states in the middle region. The tunneling current can be turned on and off by varying the Fermi energy. Tunability of resonant tunneling is realized by changing the width of the left and/or right leads and without the use of any external gates. |
| ISSN: 0957-4484 |
| Article Number: 415203 |
| DOI: 10.1088/0957-4484/20/41/415203 |
| Record 4 of 9 |
| Author(s): You, JB (You, J. B.); Zhang, XW (Zhang, X. W.); Song, HP (Song, H. P.); Ying, J (Ying, J.); Guo, Y (Guo, Y.); Yang, AL (Yang, A. L.); Yin, ZG (Yin, Z. G.); Chen, NF (Chen, N. F.); Zhu, QS (Zhu, Q. S.) |
| Title: Energy band alignment of SiO2/ZnO interface determined by x-ray photoelectron spectroscopy |
| Source: JOURNAL OF APPLIED PHYSICS, 106 (4): Art. No. 043709 AUG 15 2009 |
| Abstract: Thin SiO2 interlayer is the key to improving the electroluminescence characteristics of light emitting diodes based on ZnO heterojunctions, but little is known of the band offsets of SiO2/ZnO. In this letter, energy band alignment of SiO2/ZnO interface was determined by x-ray photoelectron spectroscopy. The valence band offset Delta E-V of SiO2/ZnO interface is determined to be 0.93 +/- 0.15 eV. According to the relationship between the conduction band offset Delta E-C and the valence band offset Delta E-V: Delta E-C=E-g(SiO2)-E-g(ZnO)-Delta E-V, and taking the room-temperature band-gaps of 9.0 and 3.37 eV for SiO2 and ZnO, respectively, a type-I band-energy alignment of SiO2/ZnO interface with a conduction band offset of 4.70 +/- 0.15 eV is found. The accurate determination of energy band alignment of SiO2/ZnO is helpful for designing of SiO2/ZnO hybrid devices and is also important for understanding their carrier transport properties. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3204028] |
| ISSN: 0021-8979 |
| Article Number: 043709 |
| DOI: 10.1063/1.3204028 |
| Record 5 of 9 |
| Author(s): Iqbal, J (Iqbal, Javed); Liu, XF (Liu, Xiaofang); Majid, A (Majid, Abdul); Yu, DP (Yu, Dapeng); Yu, RH (Yu, Ronghai) |
| Title: Narrowing of band gap and low-temperature spin glass behavior of FeNi co-doped ZnO nanowires |
| Source: EPL, 87 (5): Art. No. 57004 SEP 2009 |
| Abstract: This letter reports on the Raman, optical and magnetic properties of FeNi co-doped ZnO nanowires prepared via a soft chemical solution method. The microstructural investigations show that the NiFe co-dopants are substituted into wurtzite ZnO nanostructure without forming any secondary phase. The co-doped nanowires show a remarkable reduction of 34 nm (267.9 meV) in the optical band gap, while suppression in the deep-level defect transition in visible luminescence. Furthermore, these nanowires exhibit ferromagnetism and an interesting low-temperature spin glass behavior, which may arise due to the presence of disorder and strong interactions of frustrated spin moments of Ni and Fe co-dopants on the ZnO lattice sites. Copyright (C) EPLA, 2009 |
| ISSN: 0295-5075 |
| Article Number: 57004 |
| DOI: 10.1209/0295-5075/87/57004 |
| Record 6 of 9 |
| Author(s): Shi, HL (Shi, Hongliang); Zhang, P (Zhang, Ping); Li, SS (Li, Shu-Shen); Sun, B (Sun, Bo); Wang, BT (Wang, Baotian) |
| Title: Electronic structures and mechanical properties of uranium monocarbide from first-principles LDA plus U and GGA plus U calculations |
| Source: PHYSICS LETTERS A, 373 (39): 3577-3581 SEP 21 2009 |
| Abstract: The electronic structure, elastic constants, Poisson's ratio, and phonon dispersion curves of UC have been systematically investigated from the first-principles calculations by the projector-augmented-wave (PAW) method. In order to describe precisely the strong on-site Coulomb repulsion among the localized U 5f electrons, we adopt the local density approximation (LDA) + U and generalized gradient approximation (GGA) + U formalisms for the exchange correlation term. We systematically study how the electronic properties and elastic constants of UC are affected by the different choice of U as well as the exchange-correlation potential. We show that by choosing an appropriate Hubbard U parameter within the GGA + U approach, most of our calculated results are in good agreement with the experimental data. Therefore. the results obtained by the GGA + U with effective Hubbard parameter U chosen around 3 eV for UC are considered to be reasonable. (C) 2009 Elsevier B.V. All rights reserved. |
| ISSN: 0375-9601 |
| DOI: 10.1016/j.physleta.2009.07.074 |
| Record 7 of 9 |
| Author(s): Wang, L (Wang, L.); Zhao, L (Zhao, L.); Pan, J (Pan, J.); Zhang, W (Zhang, W.); Wang, H (Wang, H.); Zhu, H (Zhu, H.); Wang, W (Wang, W.) |
| Title: A new phototransistor with uni-travelling-carrier and optically gradual coupling properties |
| Source: OPTO-ELECTRONICS REVIEW, 17 (3): 242-246 SEP 2009 |
| Abstract: Based on appropriate combination of different band-gap InGaAsP, a new edge-coupled two-terminal double heterojunction phototransistor (ECTT-DHPT) was designed and fabricated, which is double heterojunction, free-aluminium, and works under uni-travelling-carrier mode and optically gradual coupling mode. This device is fully compatible with monolithic micro-wave integrated circuits (MMIC) and heterojunction bipolar transistor (HBT) in material and process. The DC characteristics reveal that the new ECTT-DHPT can perform good optoelectronic mix operation and linear amplification operation by optically biased at two appropriate value respectively. Responsivity of more than 52 A/W and dark current of 70 nA (when V-EC = 1 V) were obtained. |
| ISSN: 1230-3402 |
| DOI: 10.2478/s11772-008-0064-6 |
| Record 8 of 9 |
| Author(s): You, JB (You, J. B.); Zhang, XW (Zhang, X. W.); Dong, JJ (Dong, J. J.); Song, XM (Song, X. M.); Yin, ZG (Yin, Z. G.); Chen, NF (Chen, N. F.); Yan, H (Yan, H.) |
| Title: Localized-Surface-Plasmon Enhanced the 357 nm Forward Emission from ZnMgO Films Capped by Pt Nanoparticles |
| Source: NANOSCALE RESEARCH LETTERS, 4 (10): 1121-1125 OCT 2009 |
| Abstract: The Pt nanoparticles (NPs), which posses the wider tunable localized-surface-plasmon (LSP) energy varying from deep ultraviolet to visible region depending on their morphology, were prepared by annealing Pt thin films with different initial mass-thicknesses. A sixfold enhancement of the 357 nm forward emission of ZnMgO was observed after capping with Pt NPs, which is due to the resonance coupling between the LSP of Pt NPs and the band-gap emission of ZnMgO. The other factors affecting the ultraviolet emission of ZnMgO, such as emission from Pt itself and light multi-scattering at the interface, were also discussed. These results indicate that Pt NPs can be used to enhance the ultraviolet emission through the LSP coupling for various wide band-gap semiconductors. |
| ISSN: 1931-7573 |
| DOI: 10.1007/s11671-009-9366-y |
| Record 9 of 9 |
| Author(s): Wei, TB (Wei, T. B.); Hu, Q (Hu, Q.); Duan, RF (Duan, R. F.); Wei, XC (Wei, X. C.); Huo, ZQ (Huo, Z. Q.); Wang, JX (Wang, J. X.); Zeng, YP (Zeng, Y. P.); Wang, GH (Wang, G. H.); Li, JM (Li, J. M.) |
| Title: Growth of (10(1)over-bar(3)over-bar) semipolar GaN on m-plane sapphire by hydride vapor phase epitaxy |
| Source: JOURNAL OF CRYSTAL GROWTH, 311 (17): 4153-4157 AUG 15 2009 |
| Abstract: The crystalline, surface, and optical properties of the (10 (1) over bar(3) over bar) semipolar GaN directly grown on m-plane sapphire substrates by hydride vapor phase epitaxy (HVPE) were investigated. It was found that the increase of V/III ratio led to high quality (10 (1) over bar(3) over bar) oriented GaN epilayers with a morphology that may have been produced by step-flow growth and with minor evidence of anisotropic crystalline structure. After etching in the mixed acids, the inclined pyramids dominated the GaN surface with a density of 2 X 10(5) cm(-2), revealing the N-polarity characteristic. In the low-temperature PL spectra, weak BSF-related emission at 3.44eV could be observed as a shoulder of donor-bound exciton lines for the epilayer at high V/III ratio, which was indicative of obvious reduction of BSFs density. In comparison with other defect related emissions, a different quenching behavior was found for the 3.29 eV emission, characterized by the temperature-dependent PL measurement. (C) 2009 Elsevier B.V. All rights reserved. |
| ISSN: 0022-0248 |
| DOI: 10.1016/j.jcrysgro.2009.06.058 |
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