Spatially Inhomogeneous Competition between Superconductivity and the Charge Density Wave in YBa<sub>2</sub>Cu<sub>3</sub>O<sub>6.67</sub>
ORAL
Abstract
Application of magnetic field induces new charge density wave (CDW) order in the high-temperature superconductor YBa2Cu3O7−x (YBCO), which is defined here as ferro-coupled CDW (F-CDW). It can be differentiated from the conventional antiferro-coupled CDW (or AF-CDW) by their c-axis correlations. This discovery has provoked a number of questions such as how does superconductivity compete with two CDW orders? and are either of these orders responsible for the electronic reconstruction? High-energy x-ray diffraction experiements were carried out to find a clue to those questions. The intensity of F-CDW order in YBa2Cu3O6.67 was investigated as a function of magnetic field and temperature. We found that F-CDW order exists from low-field range B ~ 5 T, and regions of the sample with F-CDW order suppress superconductivity stronger than those with AF-CDW order. It implies that the superconducting state in some regions is more fragile than that in the other regions. In addition, F-CDW order has sufficiently long correlation length to explain the reconstruction of the electronic state. Our study sheds a light on the role of F-CDW order in superconducting and normal state properties of underdoped YBCO.
–
Presenters
-
Jaewon Choi
- Physik-Institut, University of Zurich