Speaker: Rahul Sharma Title: Momentum Resolved Superconducting Energy Gaps of Sr 2 RuO 4 using SI-STM Abstract: Sr 2 RuO 4 has been a focus of research since past 25 years for the possibility of correlated topological superconductivity. The key to superconducting order parameter lies with the momentum space structure of superconducting gap on each band i. Because the energy scales are so low, it has never been possible to measure the of Sr 2 RuO 4 . We have used millikelvin spectroscopic-imaging scanning tunneling microscopy (SI-STM), a technique capable of measuring for multiband superconductors with high precision to study superconducting state of Sr 2 RuO 4 . At T=90mK, we visualize a set of Bogoliubov scattering interference wavevectors consistent with gap nodes/minima, that are all closely aligned to the crystal-lattice directions on both the α- and β-bands. Taking these observations in combination with other very recent advances in theory and experiments, the BQPI signature of Sr 2 RuO 4 appears most consistent with having symmetry. Host: J. Paglione
Meeting Schedule Refreshments 1:30pm John S Toll Physics Bldg Room 1117. Please bring a reusable coffee mug.