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We characterize the properties of Ce1−xYbxRhIn5 single crystals with 0 x 1 using measurements of powder x-ray diffraction, energy dispersive x-ray spectroscopy, electrical resistivity, magnetic susceptibility, specific heat, x-ray absorption near edge structure (XANES), and neutron diffraction. The Yb valence vYb, calculated from the magnetic susceptibility and measured using XANES, decreases from 3+ at x = 0 to ∼2.1+ at xact = 0.2, where xact is the measured Yb concentration. A transition from incommensurate to commensurate antiferromagnetism is observed in neutron diffraction measurements along Q = (0.5, 0.5, l) between 0.2 xact 0.27; this narrative is supported by specific-heat measurements in which a second robust feature appears at a temperature TI (TI < TN) for the same concentration range. Magnetic susceptibility measurements also reveal features which provide additional evidence of magnetic ordering. The results of this study suggest that the evolution of the Yb valence plays a critical role in tuning the magnetic ground state of Ce1−xYbxRhIn5.
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Commensurate and incommensurate magnetic structure of the moderately frustrated antiferromagnet Li2M(WO4)2 with M = Co, Ni
We have investigated the magnetic structure of Li2Co(WO4)2 via magnetic susceptibility, and neutron diffraction measurements. Two magnetic transitions are observed in magnetic susceptibility at TN1∼9.5K and TN2∼7.2K. Neutron diffraction reveals an incommensurate magnetic order with a wave vector kICM=(∼0.46,∼0.27,∼0.24) between TN1 and TN2 and a commensurate magnetic order with a wave vector kCM=(0.5,0.25,0.25) below TN2. The magnetic periodicity in the commensurate phase is four times larger than the nuclear unit cell length along the b- and c-axis directions with a saturated magnetic moment equal to ≈2.92μB. Below TN1, the ICM wave vector for Li2Co(WO4)2 varies with decreasing temperature and locked into commensurate at TN2, whereas weaker temperature dependence of kICM=(0.46,0.17,0.33) is observed for Li2Ni(WO4)2.
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- Award ID(s):
- 1832031
- PAR ID:
- 10336001
- Date Published:
- Journal Name:
- Physical review
- Volume:
- 104
- Issue:
- 13
- ISSN:
- 2469-9950
- Page Range / eLocation ID:
- 134435
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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