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arXiv · 1406.2231

Field-induced incommensurate phase in the strong-rung spin ladder with ferromagnetic legs

H. Yamaguchi·H. Miyagai·M. Yoshida·M. Takigawa·K. Iwase·T. Ono·N. Kase·K. Araki·S. Kittaka·T. Sakakibara·T. Shimokawa·T. Okubo·K. Okunishi·A. Matsuo·Y. Hosokoshi
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Abstract

We report magnetization, specific heat, and NMR measurements of 3-Br-4-F-V [=3-(3-bromo-4-fluorophenyl)-1,5-diphenylverdazyl], a strong-rung S=1/2 Heisenberg spin ladder with ferromagnetic leg interactions. We explain the magnetic and thermodynamic properties based on the strong-rung regime. Furthermore, we find a field-induced successive phase transition in the specific heat and the nuclear spin-lattice relaxation rate 1/T1. 19F-NMR spectra for higher- and lower-temperature phases indicate partial magnetic order and incommensurate long-range order, respectively, evidencing the presence of frustration due to weak interladder couplings.

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H. Yamaguchi, H. Miyagai, M. Yoshida, M. Takigawa, K. Iwase, T. Ono, N. Kase, K. Araki, S. Kittaka, T. Sakakibara, T. Shimokawa, T. Okubo, K. Okunishi, A. Matsuo, Y. Hosokoshi. 2014-06-09. Field-induced incommensurate phase in the strong-rung spin ladder with ferromagnetic legs. https://doi.org/10.1103/physrevb.89.220402

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