Lattice collapse and quenching of magnetism in CaFe2As2 under pressure: A single crystal neutron and x-ray diffraction investigation
| Autor: | Goldman, A. I., Kreyssig, A., Prokes, K., Pratt, D. K., Argyriou, D. N., Lynn, J. W., Nandi, S., Kimber, S. A. J., Chen, Y., Lee, Y. B., Samolyuk, G., Leao, J. B., Poulton, S. J., Bud'ko, S. L., Ni, N., Canfield, P. C., Harmon, B. N., McQueeney, R. J. |
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| Rok vydání: | 2008 |
| Předmět: | |
| Zdroj: | Phys. Rev. B 79, 024513 (2009) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1103/PhysRevB.79.024513 |
| Popis: | Single crystal neutron and high-energy x-ray diffraction have identified the phase lines corresponding to transitions between the ambient-pressure tetragonal (T), the antiferromagnetic orthorhombic (O) and the non-magnetic collapsed tetragonal (cT) phases of CaFe2As2. We find no evidence of additional structures for pressures up to 2.5 GPa (at 300 K). Both the T-cT and O-cT transitions exhibit significant hysteresis effects and we demonstrate that coexistence of the O and cT phases can occur if a non-hydrostatic component of pressure is present. Measurements of the magnetic diffraction peaks show no change in the magnetic structure or ordered moment as a function of pressure in the O phase and we find no evidence of magnetic ordering in the cT phase. Band structure calculations show that the transition results in a strong decrease of the iron 3d density of states at the Fermi energy, consistent with a loss of the magnetic moment. Comment: List of authors in metadata and typos in labeling of inset in Fig. 1(a) corrected. One ref. added. No other changes |
| Databáze: | arXiv |
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