Europhys. Lett.
Volume 71, Number 6, September 2005
Page(s) 980 - 986
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 24 August 2005
Europhys. Lett., 71 (6), pp. 980-986 (2005)
DOI: 10.1209/epl/i2005-10183-2

Fractionally quantized magnetization plateaus of a spin- $\mth{(1/2)}$ ladder with different chain exchange

S. Sarkar

Department of Condensed Matter Physics, Weizmann Institute of Science Rehovot-76100, Israel

received 4 January 2005; accepted in final form 20 July 2005
published online 24 August 2005

We study a system with spin-Peierls dimerization in next-nearest-neighbor (NNN) interaction and also the presence of nearest-neighbor (NN) interaction under a magnetic field. We predict the existence of different fractionally quantized magnetization plateaus with many interesting physical properties. The effect of the frustrating NNN interaction and the role of quantum fluctuations are also explored for different magnetization plateaus. We explain more physically the gapless state of spin spectrum for small values of the frustrating NNN interaction. The transition from commensurate gapped phase to incommensurate Luttinger liquid phase is of Mott-$\delta$ type.

75.10.Jm - Quantized spin models.
75.40.Cx - Static properties (order parameter, static susceptibility, heat capacities, critical exponents, etc.).
75.45.+j - Macroscopic quantum phenomena in magnetic systems.

© EDP Sciences 2005