In the realm of energy research, a team of scientists from various institutions, including Gaetano Campi and Andrea Alimenti from the University of Rome “Tor Vergata,” Sang-Eon Lee and Luis Balicas from the National High Magnetic Field Laboratory, and Gennady Logvenov and Antonio Bianconi from the Rome International Center for Materials Science Superstripes, have made significant strides in understanding high-temperature superconductors. Their work, published in the journal Nature Communications, focuses on artificial high-temperature superlattices (AHTS) and their response to high magnetic fields.
The researchers investigated AHTS composed of quantum wells that confine interface space charge in stoichiometric Mott insulator layers (S) at the interface with overdoped normal metallic cuprate layers (N). These superlattices, with a period d and S layer thickness L, exhibit a superconducting dome when the L over d ratio is tuned. This phenomenon was predicted by quantum material design engineering quantum size effects.
To delve deeper into this behavior, the team conducted high-field magneto transport measurements up to 41 Tesla across the entire superconducting dome. Their findings revealed a universal upward-concave behavior of the temperature-dependent upper critical magnetic field in low critical temperature samples at both the rising and dropping edges of the dome. This observation provides compelling evidence for two-band superconductivity, aligning with the multigap theory used for the quantum design of the SNSN superlattices.
The measured superconducting coherence length demonstrated that atomic-scale engineering controls not only the critical temperature but also the intrinsic pair size at Fano-Feshbach resonances. This breakthrough paves the way for the development of next-generation quantum devices and offers new insights into unconventional superconductivity.
For the energy sector, this research could have practical applications in the development of more efficient and compact superconducting materials for power transmission and magnetic storage devices. The ability to control superconductivity through atomic-scale engineering could lead to significant advancements in energy infrastructure and technology.
Source: Campi, G., Alimenti, A., Lee, S.E. et al. High magnetic field response of superconductivity dome in quantum artificial High Tc superlattices with variable geometry. Nat Commun 15, 1121 (2024).
This article is based on research available at arXiv.