Pismo uredniku
Electronically induced anomaly in LO phonon dispersion of high - Tc superconductors
Slaven Barišić
Ivana Mrkonjić
Ivan Kupčić
Sažetak
Strong, electronically-induced anomaly in the spectrum of the longitudinal optical (LO) phonons propagating along the main axes of the CuO2 plane is tentatively attributed to the oxygen-oxygen charge transfer between two in-plane oxygen atoms. It is argued that this charge transfer can be large and that it is strongly coupled to the LO dimerization of the oxygens. The corresponding negative contribution to the free energy is quartic in the LO phonon amplitude, indicating the instability via the first-order phase transition, with a concomitant domain structure.
Ključne riječi
superconductivity; high-Tc cuprates; La2-xSrxCuO4; YBa2Cu3O6+x; LO phonons; oxygen-oxygen charge susceptibility; first-order phase transitions
Hrčak ID:
301562
URI
Datum izdavanja:
1.10.2001.
Posjeta: 182 *