The effect on the superconducting transition temperature of exchanging O18 for O16 in La1.85Sr0.15CuO4 has been studied. The concentration of the two isotopes has been determined by Rutherford backscattering spectroscopy and Raman spectroscopy confirmed the mass-related phonon frequency shift. The O18 substitution is found to be the same on the two O sites. Magnetic measurements of the transition temperature reveal a nonzero isotope effect (±=0.16±0.02). The exponent ± has also been calculated within a conventional electron-phonon interaction model and was found to be significantly larger.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)