We have measured the ab-plane reflectivity spectra of n-type single-crystal cuprates R1.85Ce0.15CuO4-δ (R = Nd, Eu, Gd) at temperatures from 10 to 280 K using Fourier-transform infrared (FTIR) spectroscopy. In the mid-infrared (MIR) region, Nd1.85Ce 0.15CuO4-δ (NCCO) does not exhibit pseudogap-like behavior, but Eu1.85Ce0.15CuO4-δ (ECCO) and Gd1.85Ce0.15CuO4-δ (GCCO) clearly exhibit strong pseudogap absorption between 0.15 eV and 0.4 eV. The relevant temperature range varies with the rare-earth element R via a pressure effect. The observed pseudogap evolution is well explained in terms of the antiferromagnetic phase fluctuation.
Bibliographical noteFunding Information:
This work was supported by KICOS (Contract No. 2008-8-1673 ) and by NRF (Contract No. C00511 ).
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering