Dresden 2009 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 16: Correlated Electrons: Low-dimensional Systems - Materials 1
TT 16.1: Vortrag
Dienstag, 24. März 2009, 09:30–09:45, HSZ 304
High field ESR study of the new low dimensional S=1/2 system: Cu(NO3)2 ·H2O — •M. Yehia1, E. Vavilova1,2, V. Kataev1, R. Klingeler1, O. Volkova3,4, E. Lapsheva4, V. Shutov4, O. Savelieva4, A.N. Vasiliev4, and B. Büchner1 — 1Institute for Solid State Physics, IFW Dresden, 01171 Dresden, Germany. — 2Kazan Physical Technical Institute, Russian Academy of Sciences, 420029 Kazan, Russia. — 3Institute of Radiotechnics and Electronics, 125009 Moscow, Russia. — 4Moscow State University, 119991 Moscow, Russia.
Cu(NO3)2·H2O is a new low dimensional spin system based on transition metal nitrates. It contains two-dimensional Cu2+(S = 1/2) layers separated by water molecules. ESR, magnetic susceptibility, specific heat and NMR have been measured on single crystalline samples of Cu(NO3)2·H2O. Specific heat and magnetic susceptibility data imply a phase transition possibly of antiferromagnetic (AFM) nature at TN ∼ 3.4 K. However, no long range order is observed in the temperature dependence of ESR measurables. The temperature dependence of the electron spin dynamics has been investigated by NMR. Various spin gap excitations have been observed using high field ESR. We discuss these features by considering the ground state and magnetic excitations of the orthogonal spin-dimers network which is realized in the Cu-layers of this material.