Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2007-09-07
Phys. Rev B 77, 045131 (2008)
Physics
Condensed Matter
Strongly Correlated Electrons
7 pages, 8 figures
Scientific paper
10.1103/PhysRevB.77.045131
We report on phonon properties and electronic transitions in CaCu3Ti4O12, a material which reveals a colossal dielectric constant at room temperature without any ferroelectric transition. The results of far- and mid-infrared measurements are compared to those obtained by broadband dielectric and millimeter-wave spectroscopy on the same single crystal. The unusual temperature dependence of phonon eigenfrequencies, dampings and ionic plasma frequencies of low lying phonon modes are analyzed and discussed in detail. Electronic excitations below 4 eV are identified as transitions between full and empty hybridized oxygen-copper bands and between oxygen-copper and unoccupied Ti 3d bands. The unusually small band gap determined from the dc-conductivity (~200 meV) compares well with the optical results.
Ebbinghaus S. G.
Kant Ch.
Krohns S.
Loidl Alois
Lunkenheimer P.
No associations
LandOfFree
Broadband dielectric response of CaCu3Ti4O12: From dc to the electronic transition regime does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Broadband dielectric response of CaCu3Ti4O12: From dc to the electronic transition regime, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Broadband dielectric response of CaCu3Ti4O12: From dc to the electronic transition regime will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-467343