Superconducting Density of States of PtPb4
PtPb4 is a type II superconductor with a bulk critical temperature Tc ≈ 3 K and an upper critical field of Hc2 = 0.36T. PtPb4 is related to non-superconducting PtSn4, which presents nodal arc states at the surface. Here, we measure the superconducting density of states of PtPb4 using millikelvin Sca...
| Authors: | , , , , , , , |
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| Format: | article |
| Publication Date: | 2025 |
| Country: | España |
| Institution: | Universidad Autónoma de Madrid |
| Repository: | Biblos-e Archivo. Repositorio Institucional de la UAM |
| Language: | English |
| OAI Identifier: | oai:repositorio.uam.es:10486/720047 |
| Online Access: | http://hdl.handle.net/10486/720047 https://dx.doi.org/10.1007/s10948-025-06995-8 |
| Access Level: | Open access |
| Keyword: | Superconductivity Critical temperature Twinning planes Binary intermetallic compounds Scanning Tunneling Microscopy Very low temperatures Física |
| Summary: | PtPb4 is a type II superconductor with a bulk critical temperature Tc ≈ 3 K and an upper critical field of Hc2 = 0.36T. PtPb4 is related to non-superconducting PtSn4, which presents nodal arc states at the surface. Here, we measure the superconducting density of states of PtPb4 using millikelvin Scanning Tunneling Microscopy (STM). We observe a fully opened superconducting gap of = 0.48 meV similar to expectations from Bardeen, Cooper and Schrieffer (BCS) theory (0 = 1.76kB Tc = 0.49 meV). Measurements under magnetic fields applied perpendicular to the surface show a spatially inhomogeneous gap structure, presenting superconducting signatures at fields as high as 1.5 T, significantly above Hc2 = 0.36 T. On some locations, we find that the superconducting density of states does not vanish above Tc. We can find signatures of a superconducting gap up to 5 K. We discuss possible reasons for the observation of superconducting properties above Tc andHc2, emphasizing the role played by structural defects |
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