Large Isotope Effect on the Pseudogap in the High-Temperature SuperconductorHoBa2Cu4O8

Autor:	Albert Furrer, H. Mutka, K. Conder, S. Janssen, K. Müller, Joël Mesot, D. Rubio Temprano
Rok vydání:	2000
Předmět:	Superconductivity High-temperature superconductivity Materials science Condensed matter physics Isotope Isotopes of copper General Physics and Astronomy chemistry.chemical_element Copper Inelastic neutron scattering law.invention chemistry law Kinetic isotope effect Pseudogap
Zdroj:	Physical Review Letters. 84:1990-1993
ISSN:	1079-7114 0031-9007
DOI:	10.1103/physrevlett.84.1990
Popis:	The copper isotope effect (63Cu vs.65Cu) on the relaxation rate of crystal-field excitations in the slightly underdoped high-temperature superconductor HoBa2Cu4O8 has been investigated by inelastic neutron scattering. For the 63Cu compound there is clear evidence for the opening of an electronic gap in the normal state at T * ≈ 160 K far above Tc = 79.0 K. Upon substitution of 63Cu by 65Cu, Tc decreases marginally to 78.6 K, whereas T * is increased to about 185 K. This large copper isotope shift ΔT * (Cu) = T * (65Cu) - T * (63Cu) ≈ 25 K - together with the corresponding oxygen isotope shift ΔT * (O) = T * (18O) - T * (16O) ≈ 50 K found in an earlier investigation - suggests that phonons or lattice fluctuations involving both the copper and the oxygen ions are important for the pairing mechanism in high-Tc materials.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::fbd423a7a8886dca0ec1247638fddf1d https://doi.org/10.1103/physrevlett.84.1990 Zobrazit plný text záznamu