When low- and high-energy electronic responses meet in cuprate superconductors
2007 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 75, no 22, 224508- p.Article in journal (Refereed) Published
The existence of coherent quasiparticles near the Fermi energy in the low-temperature state of high-temperature superconductors has been well established by angle-resolved photoemission spectroscopy (ARPES). We present a study of La1.83Sr0.17CuO4 in the superconducting state and report an abrupt change in the quasiparticle spectral function, as we follow the dispersion of the ARPES signal from the Fermi energy to 0.6 eV. The interruption in the quasiparticle dispersion separates coherent quasiparticle peaks at low energies from broad incoherent excitations at high energies. We find that the boundary between these low-energy and high-energy features exhibits a cosine-shaped momentum dependence, reminiscent of the superconducting d-wave gap. Further intriguing similarities between characteristics of the incoherent excitations and quasiparticle properties suggest a close relation between the electronic response at high and low energies in cuprate superconductors.
Place, publisher, year, edition, pages
2007. Vol. 75, no 22, 224508- p.
HIGH-TEMPERATURE SUPERCONDUCTORS; T-C SUPERCONDUCTORS; EXCITATIONS; OXIDES; MODE
Other Engineering and Technologies not elsewhere specified
IdentifiersURN: urn:nbn:se:kth:diva-8065DOI: 10.1103/PhysRevB.75.224508ISI: 000247624800090ScopusID: 2-s2.0-34347358510OAI: oai:DiVA.org:kth-8065DiVA: diva2:13286
QC 201008102007-12-122007-12-122010-08-10Bibliographically approved