High-pressure Tuning Of Valence And Magnetic Interactions In Eu 0.5yb 0.5ga 4

Pressure-induced changes in valence and magnetic ordering are observed in a Eu 0.5Yb 0.5Ga 4 compound by means of element selective x-ray absorption spectroscopy at Eu and Yb L 3 edges. Concomitant Eu and Yb valence transitions towards a 3+ state, together with an antiferromagnetic to ferromagnetic transition, are observed with applied pressures up to 30 GPa. With the support of density functional theory calculations, we argue that hybridization between (Eu/Yb)-5d and Ga orbitals regulates the valence and magnetic exchange interactions in this system. © 2012 American Physical Society.8524Bobev, S., Bauer, E.D., Thompson, J., Sarrao, J.L., (2004) J. Magn. Magn. Mater., 277, p. 236. , JMMMDC 0304-8853 10.1016/j.jmmm.2003.11.005Loula, G., Da Silva, L., Dos Santos, A., Medina, A., Gandra, F., (2008) Physica B: Condens. Matter, 403, p. 946. , PHYBE3 0921-4526 10.1016/j.physb.2007.10.285Vries, J.D., Thiel, R., Buschow, K., (1985) Physica B+C, 128, p. 265. , PHBCDQ 0378-4363 10.1016/0378-4363(85)90001-4Sun, L., Guo, J., Chen, G., Chen, X., Dong, X., Lu, W., Zhang, C., Zhang, S., (2010) Phys. Rev. B, 82, p. 134509. , PRBMDO 1098-0121 10.1103/PhysRevB.82.134509Cooley, J.C., Aronson, M.C., Sarrao, J.L., Fisk, Z., (1997) Phys. Rev. B, 56, p. 14541. , PRBMDO 1098-0121 10.1103/PhysRevB.56.14541Shannon, J.R., Sienko, M.J., (1972) Inorg. Chem., 11, p. 904. , INOCAJ 0020-1669 10.1021/ic50110a056Guy, C., Von Molnar, S., Etourneau, J., Fisk, Z., (1980) Solid State Commun., 33, p. 1055. , SSCOA4 0038-1098 10.1016/0038-1098(80)90316-6Schütz, G., Wagner, W., Wilhelm, W., Kienle, P., Zeller, R., Frahm, R., Materlik, G., (1987) Phys. Rev. Lett., 58, p. 737. , PRLTAO 0031-9007 10.1103/PhysRevLett.58.737Lang, J.C., Srajer, G., (1995) Rev. Sci. Instrum., 66, p. 1540. , RSINAK 0034-6748 10.1063/1.1145902Dadashev, A., Pasternak, M.P., Rozenberg, G.K., Taylor, R.D., (2001) Rev. Sci. Instrum., 72, p. 2633. , RSINAK 0034-6748 10.1063/1.1370561Syassen, K., (2008) High Press. Res., 28, p. 75. , HPRSEL 0895-7959 10.1080/08957950802235640Haskel, D., Tseng, Y.C., Lang, J.C., Sinogeikin, S., Instrument for x-ray magnetic circular dichroism measurements at high pressures (2007) Review of Scientific Instruments, 78 (8), p. 083904. , DOI 10.1063/1.2773800Blaha, P., Schwarz, K., Madsen, G., Kvasnicka, D., Luitzr, J., (2001) WIEN2k, An Augmented Plane Wave + Local Orbitals Program for Calculating Crystal Properties, , Technische Universität WienLang, J.C., Srajer, G., Detlefs, C., Goldman, A.I., König, H., Wang, X., Harmon, B.N., McCallum, R.W., (1995) Phys. Rev. Lett., 74, p. 4935. , PRLTAO 0031-9007 10.1103/PhysRevLett.74.4935Pettifer, R.F., Collins, S.P., Laundy, D., Quadrupole transitions revealed by Borrmann spectroscopy (2008) Nature, 454 (7201), pp. 196-199. , DOI 10.1038/nature07099, PII NATURE07099Souza-Neto, N.M., Haskel, D., Tseng, Y.-C., Lapertot, G., (2009) Phys. Rev. Lett., 102, p. 057206. , PRLTAO 0031-9007 10.1103/PhysRevLett.102.057206Lechner, R.T., Springholz, G., Schulli, T.U., Stangl, J., Schwarzl, T., Bauer, G., Strain induced changes in the magnetic phase diagram of metamagnetic heteroepitaxial EuSe/PbSe 1-xTe x multilayers (2005) Physical Review Letters, 94 (15), pp. 1-4. , http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype= pdf&id=PRLTAO000094000015157201000001&idtype=cvips, DOI 10.1103/PhysRevLett.94.157201, 157201Anderson, P.W., (1950) Phys. Rev., 79, p. 350. , PHRVAO 0031-899X 10.1103/PhysRev.79.350Kasuya, T., (1956) Prog. Theor. Phys., 16, p. 45. , PTPKAV 0033-068X 10.1143/PTP.16.45Yosida, K., (1957) Phys. Rev., 106, p. 893. , PHRVAO 0031-899X 10.1103/PhysRev.106.893Ruderman, M.A., Kittel, C., (1954) Phys. Rev., 96, p. 99. , PHRVAO 0031-899X 10.1103/PhysRev.96.99Haskel, D., Lee, Y.B., Harmon, B.N., Islam, Z., Lang, J.C., Srajer, G., Mudryk, Ya., Pecharsky, V.K., Role of Ge in bridging ferromagnetism in the giant magnetocaloric Gd5(Ge1-xSix)4 alloys (2007) Physical Review Letters, 98 (24), p. 247205. , http://oai.aps.org/oai?verb=GetRecord&Identifier=oai:aps.org: PhysRevLett.98.247205&metadataPrefix=oai_apsmeta_2, DOI 10.1103/PhysRevLett.98.24720