Probing inhomogeneity in high-temperature superconductors


  • Miguel Antonio Sulañgi National Institute of Physics, University of the Philippines Diliman


It is known that the high-temperature superconductors are strikingly inhomogeneous. I summarize here key results from recent theoretical and experimental studies of these materials, all involving their inhomogeneity as an important element. First, I present results on iron-based superconductors. Employing a phase-sensitive quasiparticle scattering interference-based technique optimized for disordered materials, the particular pairing symmetries of FeSe and LiFeAs are deduced from scanning tunneling microscopy (STM) experiments. Second, I report recent work on overdoped cuprates. Using STM, the emergence of an unusual "puddly" form of superconductivity in this regime is visualized, with gaps persisting even when superconductivity has disappeared, consistent with a model of superconducting puddles embedded in a metallic matrix. Finally, I show theoretical results showing how phase fluctuations can be detected via angle-resolved photoemission spectroscopy, and how the amount of inhomogeneity in the superfluid density of the cuprates can be estimated from these experiments.

About the Speaker

Miguel Antonio Sulañgi, National Institute of Physics, University of the Philippines Diliman

Miguel Sulañgi is an Associate Professor at the National Institute of Physics at the University of the Philippines Diliman. His research work is centered on theoretical condensed matter physics, with a current focus on unconventional superconductivity, strongly correlated electron systems, and disorder, and his work has frequently involved collaborations with experimentalists. He obtained his undergraduate degree from Ateneo de Manila University and his graduate degrees from Johns Hopkins University (M.A.) and Leiden University (Ph.D.), where he performed his dissertation research under the supervision of Jan Zaanen. Prior to joining NIP, he was a postdoctoral associate in Peter Hirschfeld's group at the University of Florida, and spent time as a visiting researcher at SLAC National Accelerator Laboratory.



Article ID



Invited Presentations



How to Cite

MA Sulañgi, Probing inhomogeneity in high-temperature superconductors, Proceedings of the Samahang Pisika ng Pilipinas 40, SPP-2022-INV-1G-01 (2022). URL: