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We demonstrate the switching on and off of spatial solitons in a semiconductor microresonator by injection of light coherent
with the background illumination. The results give evidence that the formation of the solitons and their switching are not
limited by thermal processes.
Received: 11 February 2002 / Revised version: 25 April 2002 / Published online: 8 August 2002 相似文献
73.
A.C. Mofor F. Reuss A. El-Shaer R. Kling E. Schlenker A. Bakin H. Ahlers U. Siegner S. Sievers M. Albrecht W. Schoch W. Limmer J. Eisenmenger T. Mueller A. Huebel G. Denninger P. Ziemann A. Waag 《Applied Physics A: Materials Science & Processing》2007,88(1):161-166
Doping ZnO with transition metals (TM) is an obvious approach to produce diluted magnetic semiconductors for magnetoelectronic
and spintronic applications. We have carried out experimental studies on the fabrication and characterisation of Mn-doped
ZnO layers and V-doped ZnO layers and nanorods, the results of which are reviewed in this paper. From SQUID measurements,
both epitaxial and implanted ZnMnO layers show paramagnetic behaviour. Epitaxial ZnVO layers show ferromagnetic SQUID signals,
but the presence of any secondary phases in the ZnVO layers may not be ruled out. We also show that the used Al2O3 substrates produce a ferromagnetic SQUID signal, that complicates the analysis of magnetisation data and hence the confirmation
of ferromagnetism only from SQUID results.
PACS 75.50.Pp; 85.75.-d; 81.05.Dz; 75.30.-m; 75.60.Nt; 75.70.-i 相似文献
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Two novel tridentate dinucleating ligands containing benzimidazole were prepared, 1,3-bis(2-benzimidazolyl)-2-propanol (Hbbp, 1) and 1,5-bis(2-benzimidazolyl)-3-pentanol (Hbbpen, 2). Their complexing properties toward copper were studied in order to obtain structural and functional models for catechol oxidases. Syntheses and crystal structures of dinuclear Cu(II) complexes derived from these ligands are reported. [Cu(2)bbp(2)](ClO(4))(2).2MeOH, 3, crystallizes in the triclinic space group P&onemacr; with the following unit cell parameters: a = 7.702(3) ?, b = 10.973(6) ?, c = 12.396(6) ?, alpha = 100.59(4) degrees, beta = 99.02(4) degrees, gamma = 98.90(4) degrees, V = 998.7(8) ?(3), and Z = 1. [Cu(2)bbpen(2)](ClO(4))(2).3MeOH, 4, crystallizes in the orthorhombic space group Pccn, with the following unit cell parameters: a = 17.478(9) ?, b = 18.795(8) ?, c = 13.888(6) ?, V = 4562.2(4) ?(3), and Z = 4. Magnetic susceptibility measurements in the temperature ranges 4.6-459 K (3) and 4.6-425 K (4) indicate an antiferromagnetic coupling between the Cu(II) centers of both complexes. In order to determine the structures of the complexes in solution, XAS spectra (EXAFS and XANES) were recorded in the solid state and in solution. The interpretation of these data, including multiple scattering calculations, together with UV-vis titrations, shows that the complexes have the same structure in the crystalline state as well as in methanolic solution. Complex 4 is able to oxidize 3,5-di-tert-butylcatechol (3,5-DTBC) to the quinone (catecholase activity). This reaction was also studied by XAS and UV-vis spectroscopy. These measurements reveal the reduction of Cu(II) to Cu(I) accompanied by a decrease of the coordination number. 相似文献
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