Magnetization Process of the Triangular- and Kagome-Lattice Antiferromagnets

The S = 1/2 kagome- and triangular-lattice Heisenberg antiferromagnets are investigated under a magnetic field using the numerical-diagonalization method[1]. A procedure is proposed to extract data points with very small finite-size deviations using the numerical-diagonalization results for capturing the magnetization curve. For the triangular-lattice antiferromagnet, the plateau edges at one-third the height of the saturation and the saturation field are successfully estimated. This study additionally presents results of magnetization process for a 45-site cluster of the kagome-lattice antiferromagnet; the present analysis suggests that the plateau does not open at one-ninth the height of the saturation.In addition the quantum phase transition of the triangular-lattice antiferromagnet at the 1/3 magnetization with respect to the next-nearest-neighbor interaction[2].
[1]H. Nakano and T. Sakai, J. Phys. Soc. Jpn. 87 (2018) 063706
[2]H. Nakano and T. Sakai, J. Phys. Soc. Jpn. 86 (2017) 114705