STM Study of the High-Tc Order Parameter under Spin Injection
Abstract
High-Tc superconductivity can be systematically suppressed by the injection of a spin-polarized current. This effect has recently been observed in epitaxial cuprate/manganite thin-film heterostructures, and attributed to dynamic magnetic pair breaking by spin-polarized quasiparticles. In this talk I will report on a novel technique using STM spectroscopy to study how the high-Tc order parameter in superconducting YBa2Cu3O7-x (YBCO) evolves under quasiparticle spin-injection from ferromagnetic La0.7Ca0.3MnO3. The spectroscopy measurements, made on either optimally-doped or under-doped YBCO at 4.2K, indicate the predominant d-wave order parameter to remain time-reversal invariant as it is suppressed by the spin injection. These results are discussed vis-à-vis recent experimental work suggesting field-dependent time-reversal symmetry breaking in YBCO, and as part of a general search for quantum critical points in the high-Tc phase diagram.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2003
- Bibcode:
- 2003APS..MARA20003W