caa a22 4500 445381507 CHVBK 20180317143018.0 cr unu---uuuuu 170323e20110101xx s 000 0 eng 10.1007/s10948-010-0965-8 doi (NATIONALLICENCE)springer-10.1007/s10948-010-0965-8 A Novel Plateau in the Magnetization Curve of the Alternating Heisenberg Chain [Elektronische Daten] [M. Shahri Naseri, S. Mahdavifar, S. FarjamiShayesteh] At zero temperature, the effect of a uniform magnetic field on an alternating antiferromagnetic-ferromagnetic (AF-F) spin-1/2 chain is studied using the numerical Lanczos method. The alternating model is defined as an alternating AF-F Heisenberg chain with the space-modulated dominant antiferromagnetic exchange. A detailed numerical analysis of the low energy excitation spectrum is presented. The energy gap, the magnetization and the string order parameter of the system are calculated for finite chains. It is found that the space modulation on the antiferromagnetic exchange induced two new gaps in the spectrum. In these new gapped regions, the magnetization shows two nonzero plateaus at the values 1/3 and 2/3 of the saturation magnetization. Springer Science+Business Media, LLC, 2010 Magnetization plateau nationallicence Lanczos method nationallicence Alternating chain nationallicence Quantum phase transition nationallicence Shahri Naseri M. Department of Physics, University of Guilan, 41335-1914, Rasht, Iran aut Mahdavifar S. Department of Physics, University of Guilan, 41335-1914, Rasht, Iran aut FarjamiShayesteh S. Department of Physics, University of Guilan, 41335-1914, Rasht, Iran aut Journal of Superconductivity and Novel Magnetism Springer US; http://www.springer-ny.com 24/1-2(2011-01-01), 735-739 1557-1939 24:1-2<735 2011 24 10948 https://doi.org/10.1007/s10948-010-0965-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10948-010-0965-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Shahri Naseri M. Department of Physics, University of Guilan, 41335-1914, Rasht, Iran aut NATIONALLICENCE 700 1- Mahdavifar S. Department of Physics, University of Guilan, 41335-1914, Rasht, Iran aut NATIONALLICENCE 700 1- FarjamiShayesteh S. Department of Physics, University of Guilan, 41335-1914, Rasht, Iran aut NATIONALLICENCE 773 0- Journal of Superconductivity and Novel Magnetism Springer US; http://www.springer-ny.com 24/1-2(2011-01-01), 735-739 1557-1939 24:1-2<735 2011 24 10948 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer