Abstract
We explore bulk superconducting phase in single crystals of the Dirac material LaCuSb2 prepared by the self-flux method. Magnetization, muon spin relaxation measurements, and density functional theory, show the Dirac nodal line Fermi surfaces give rise to type-II superconductivity for magnetic fields applied along the a-axis, and type-I superconductivity for fields along the c-axis. Both chemical and hydrostatic pressure drastically suppress the superconducting transition. We find multiband superconductivity evidenced by a precipitous drop in the electronic specific heat capacity and high-pressure susceptibility for T* < Tc/3. Our work demonstrates dirty-limit, weak-coupling multiband superconductivity in LaCuSb2, and highlights the role of Dirac fermions on its anisotropic character.
| Original language | English |
|---|---|
| Pages (from-to) | 1685-1694 |
| Number of pages | 10 |
| Journal | Materials Advances |
| Volume | 6 |
| Issue number | 5 |
| DOIs | |
| State | Published - Jan 31 2025 |
| Externally published | Yes |
Funding
It is a great pleasure to celebrate the distinguished scientific career of Professor T. T. M. Palstra. Collin would like to thank Thom for a long-lasting scientific friendship that started with an inspiring collaboration on superconductivity and magnetism in URu2Si2 at Risø and was fortified during an exciting period of discovery at Bell Labs. Congratulations Thom and best wishes! This work was supported as part of the Institute for Quantum Matter, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award DE-SC0019331. C. J. L. acknowledges the support of the William Gardner Fellowship. The 3He MPMS was funded by the National Science Foundation, Division of Materials Research, Major Research Instrumentation Program, under Award 1828490. The superconducting fitness analysis was supported by the NSF CAREER grant DMR-1848349; JZ also acknowledges the support from the JHU Theoretical Interdisciplinary Physics and Astronomy Center. Research at McMaster University was supported by the Natural Sciences and Engineering Research Council (GML). The high pressure measurements were funded by KAKENHI (no. JP19H00648), JST-Mirai Program (no. JPMJMI20A1), JST-CREST (no. JPMJCR18T3 and JPMJCR15Q5). We would like to thank Bassam Hitti and Sarah Dunsiger for their assistance during the μSR experiment; Lisa Pogue for her preliminary DFT work; and Yishu Wang for her assistance with resistivity measurements. It is a great pleasure to celebrate the distinguished scientific career of Professor T. T. M. Palstra. Collin would like to thank Thom for a long-lasting scientific friendship that started with an inspiring collaboration on superconductivity and magnetism in URuSi at Risø and was fortified during an exciting period of discovery at Bell Labs. Congratulations Thom and best wishes! This work was supported as part of the Institute for Quantum Matter, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award DE-SC0019331. C. J. L. acknowledges the support of the William Gardner Fellowship. The 3He MPMS was funded by the National Science Foundation, Division of Materials Research, Major Research Instrumentation Program, under Award 1828490. The superconducting fitness analysis was supported by the NSF CAREER grant DMR-1848349; JZ also acknowledges the support from the JHU Theoretical Interdisciplinary Physics and Astronomy Center. Research at McMaster University was supported by the Natural Sciences and Engineering Research Council (GML). The high pressure measurements were funded by KAKENHI (no. JP19H00648), JST-Mirai Program (no. JPMJMI20A1), JST-CREST (no. JPMJCR18T3 and JPMJCR15Q5). We would like to thank Bassam Hitti and Sarah Dunsiger for their assistance during the μSR experiment; Lisa Pogue for her preliminary DFT work; and Yishu Wang for her assistance with resistivity measurements. 2 2