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arXiv · 0807.3380

μSR-detection of the soft-mode toward the exotic magnetic ground state in bond-disordered quantum spin system IPA-Cu(Cl$_{0.35}$Br$_{0.65}$)$_3$

Takayuki Goto·Takao Suzuki·Keishi Kanada·Takehiro Saito·Akira Oosawa·Isao Watanabe·Hirotaka Manaka
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Abstract

The spin-gap system with a bond-disorder (CH3)2CHNH3-Cu(ClxBr1-x)3 is reported by experiments on macroscopic quantities of the uniform susceptibility and the specific heat to show a magnetic order at low temperatures when the value of x is within the limited region between 0.44 and 0.87, and otherwise a gapped behavior. We have investigated microscopically the ground state of the sample with x=0.35 by muon spin relaxation (mSR) to observe that the frequency spectrum of the spin fluctuation tends to concentrate around zero energy as lowering temperatures. This behavior was interpreted as the soft-mode toward the possible magnetic phase transition at absolute zero.

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Takayuki Goto, Takao Suzuki, Keishi Kanada, Takehiro Saito, Akira Oosawa, Isao Watanabe, Hirotaka Manaka. 2008-07-22. μSR-detection of the soft-mode toward the exotic magnetic ground state in bond-disordered quantum spin system IPA-Cu(Cl$_{0.35}$Br$_{0.65}$)$_3$. https://doi.org/10.1103/physrevb.78.054422

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