We have studied the electronic structure of FeSe1-xTex and Ir1-xPtxTe 2 using photoemission spectroscopy. For FeSe1-xTex , angle-resolved photoemission results indicate that the Fe 3d yz/zx orbital degeneracy at F point and orbitally induced Peierls effect in the tetragonal lattice play important roles for the superconductivity. It is suggested that the Jahn-Teller instability of the yz/zx states couples with local lattice distortion derived from the Te substitution for Se and provides an inhomogeneous electronic state. Photoemission results of IrTe 2 with triangular lattice are also consistent with the orbitally induced Peierls scenario. The Pt substitution for Ir suppresses the static band Jahn-Teller effect and induces an inhomogeneous electronic state in which orbital (or bond or nematic) fluctuations may help superconductivity through the Peierls effect. ©Springer Science+Business Media, LLC 2012.
Orbital degeneracy, Jahn-Teller effect, and superconductivity in transition-metal chalcogenides / T., Mizokawa; T., Sudayama; Y., Wakisaka; D., Ootsuki; M., Imaizumi; T., Noji; Y., Koike; S., Pyon; K., Kudo; M., Nohara; H., Anzai; M., Arita; H., Namatame; M., Taniguchi; Saini, Naurang Lal. - In: JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM. - ISSN 1557-1939. - STAMPA. - 25:5(2012), pp. 1343-1346. [10.1007/s10948-012-1626-x]
Orbital degeneracy, Jahn-Teller effect, and superconductivity in transition-metal chalcogenides
SAINI, Naurang Lal
2012
Abstract
We have studied the electronic structure of FeSe1-xTex and Ir1-xPtxTe 2 using photoemission spectroscopy. For FeSe1-xTex , angle-resolved photoemission results indicate that the Fe 3d yz/zx orbital degeneracy at F point and orbitally induced Peierls effect in the tetragonal lattice play important roles for the superconductivity. It is suggested that the Jahn-Teller instability of the yz/zx states couples with local lattice distortion derived from the Te substitution for Se and provides an inhomogeneous electronic state. Photoemission results of IrTe 2 with triangular lattice are also consistent with the orbitally induced Peierls scenario. The Pt substitution for Ir suppresses the static band Jahn-Teller effect and induces an inhomogeneous electronic state in which orbital (or bond or nematic) fluctuations may help superconductivity through the Peierls effect. ©Springer Science+Business Media, LLC 2012.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
