Browsing Τμήμα Μηχανικών Μηχανολογίας και Κατασκευαστικής / Department of Mechanical and Manufacturing Engineering by Author "Lappas, A."
Now showing items 1-6 of 6
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Article
Effect of vacancy doping on the Haldane spin-liquid state in PbNi2-xMgxV2O8
Zorko, A.; Arčon, D.; Lappas, A.; Giapintzakis, John; Saylor, C.; Brunel, L. C. (2002)The effect of spin-vacancy doping on the ground state of the quasi-one-dimensional S=1 quantum antiferromagnet PbNi2V2O8 is studied by X band as well as high-field ESR. A very broad ESR line is observed at low temperatures ...
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Article
Impurity-induced antiferromagnetic order in the Haldane-gap compound (formula presented) (formula presented)
Lappas, A.; Alexandrakis, V.; Giapintzakis, John; Pomjakushin, V.; Prassides, K.; Schenck, A. (2002)An investigation of the effect of nonmagnetic Mg doping in the Haldane gap system (formula presented) is presented. Specifically, the magnetic properties of the quasi-one-dimensional compound (formula presented) (formula ...
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Impurity-induced antiferromagnetic order in the Haldane-gap compound PbNi2-xMgxV2O8 (x=0.24)
Lappas, A.; Alexandrakis, V.; Giapintzakis, John; Pomjakushin, V.; Prassides, K.; Schenck, A. (2002)An investigation of the effect of nonmagnetic Mg doping in the Haldane gap system PbNi2V2O8 is presented. Specifically, the magnetic properties of the quasi-one-dimensional compound PbNi2-xMgxV2O8 (x =0.24), located in the ...
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Article
Near critical behavior in the two-dimensional spin-gap system SrCu2(BO3)2
Zorko, A.; Arčon, D.; Lappas, A.; Giapintzakis, John (2002)The temperature dependence of the powdered X-band ESR spectra has been measured in a two-dimensional spin-gap system SrCu2(BO3)2 in the temperature range between 5 and 300 K. The spectra are composed of two overlapping ...
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Relations of crystal structure to magnetic properties in the quasi-one-dimensional compound PbNi1.88Mg0.12V 2O8
Mastoraki, I.; Lappas, A.; Giapintzakis, John; Többens, D.; Hernández-Velasco, J. (2004)The crystal structure of the quasi-one-dimensional oxide PbNi 1.88Mg0.12V2O8 has been studied by Rietveld analysis of combined high-resolution neutron and X-ray powder diffraction data at 300K and at low temperatures. The ...
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Article
Spin-gap and antiferromagnetic correlations in low-dimensional PbNi2-xAxV2O8 compounds (A = Mg, Co)
Mastoraki, I.; Lappas, A.; Schneider, R.; Giapintzakis, John (2002)The effect of the impurity doping in the quantum-spin chains of the PbNi2V2O8 Haldane-gap compound is studied. We report elastic neutron scattering and bulk magnetic susceptibility measurements on the quasi-one-dimensional ...