Public Abstract

DE-SC0004890: Quantum Materials: Magnetism, Spin-Orbit Coupling and Superconductivity

Award Status: Active

Institution: Research Foundation for the State University of New York d/b/a RFSUNY - University at Buffalo, Amherst, NY
UEI: LMCJKRFW5R81
DUNS: 038633251

Most Recent Award Date: 07/15/2026
Number of Support Periods: 16
PM: Mewes, Claudia

Current Budget Period: 12/15/2025 - 12/14/2026
Current Project Period: 12/15/2025 - 12/14/2028
PI: Zutic, Igor

Supplement Budget Period: N/A

Public Abstract

Quantum Materials: Magnetism, Spin-Orbit Coupling, and Superconductivity Principal Investigator: Igor Zutic, University at Buffalo, Amherst, NY In 2016 Basic Research Needs Workshop on Quantum Materials for Energy Relevant Technology, organized by the US Department of Energy, quantum materials are defined as solids with exotic physical properties, arising from the quantum mechanical properties of their constituent electrons. We propose to seek how these exotic physical properties can be realized even in heterostructures made of common materials, with possible implications from energy-efficient electronics to hardware implementation of artificial intelligence. The reduced dimensionality of the building blocks of such heterostructures and the improved interfacial quality enables using proximity effects. A given material can be transformed to acquire properties of its neighbors and become superconducting, magnetic, topologically nontrivial, or have enhanced spin-orbit coupling. In the normal state bound electron-hole states, also called excitons, are transformed by magnetic, spin orbit coupling, and charge-density proximity effects, as well as by the change in the band topology. Studying the transformations requires going beyond the usual single-particle picture for proximity effects. Resulting predictions will be leveraged for novel manifestations of excitonic properties using the Bethe-Salpeter equation to serve as a benchmark in expanding capabilities of the first-principles open-source package Questaal. This will be a collaboration with its principal developer, Mark van Schilfgaarde at the National Laboratory of the Rockies and the principal investigator’s graduate student, Denzel Ayala, who is co-mentored by van Schilfgaarde. While Questaal has a powerful Green’s function formulation, providing highly accurate calculations beyond density-functional theory, the proper inclusion of spin orbit coupling in Questaal’s implementation of the Bethe-Salpeter equation is still missing and will be addressed in this research project. Unlike prior work showing robust topological protection in junctions with kink states, it is suggested that junctions are not required to achieve enhanced topological robustness. The formation of topological kink states at antiferromagnetic domain walls could be observed through conductance. The understanding of proximity effects will be extended to all-epitaxial Iron/Magnesium Oxide/Vanadium (Fe/MgO/V) junctions. Collaborations with experimental groups are planned. While Fe/MgO is a building block for commercial spintronic applications, surprisingly, the normal-state conductance of Fe/MgO/V-based junctions is dominated by the orbital-symmetry-controlled spin orbit coupling rather than by the insulating MgO barrier. These peculiar manifestations appear to be related to the remarkable superconducting manifestation of the shot noise, the consequence of charge quantization, orders of magnitude larger than theoretically expected possible. Preliminary results suggest that V, as the parent conventional spin-singlet superconductor, leads to the proximity-induced spin-triplet superconductivity in Fe that appears independent of the parent V. A theoretical framework will be developed to explain how proximity effects could transform a single superconductor to act as a Josephson junction with two independent superconductors, where giant shot noise was previously observed. The aim is to establish the method of shot noise spectroscopy as a versatile probe for materials design and emergent phenomena in various proximity effects. The research in this project directly addresses two of the Department of Energy’s Grand Challenges: Controlling materials processes at the level of electrons and establishing unique properties of matter emerging from complex correlations of the electronic constituents.

Quantum Materials: Magnetism, Spin-Orbit Coupling, and Superconductivity

Principal Investigator: Igor Zutic, University at Buffalo, Amherst, NY

In 2016 Basic Research Needs Workshop on Quantum Materials for Energy Relevant Technology, organized by the US Department of Energy, quantum materials are defined as solids with exotic physical properties, arising from the quantum mechanical properties of their constituent electrons. We propose to seek how these exotic physical properties can be realized even in heterostructures made of common materials, with possible implications from energy-efficient electronics to hardware implementation of artificial intelligence. The reduced dimensionality of the building blocks of such heterostructures and the improved interfacial quality enables using proximity effects. A given material can be transformed to acquire properties of its neighbors and become superconducting, magnetic, topologically nontrivial, or have enhanced spin-orbit coupling.

In the normal state bound electron-hole states, also called excitons, are transformed by magnetic, spin orbit coupling, and charge-density proximity effects, as well as by the change in the band topology. Studying the transformations requires going beyond the usual single-particle picture for proximity effects. Resulting predictions will be leveraged for novel manifestations of excitonic properties using the Bethe-Salpeter equation to serve as a benchmark in expanding capabilities of the first-principles open-source package Questaal. This will be a collaboration with its principal developer, Mark van Schilfgaarde at the National Laboratory of the Rockies and the principal investigator’s graduate student, Denzel Ayala, who is co-mentored by van Schilfgaarde. While Questaal has a powerful Green’s function formulation, providing highly accurate calculations beyond density-functional theory, the proper inclusion of spin orbit coupling in Questaal’s implementation of the Bethe-Salpeter equation is still missing and will be addressed in this research project. Unlike prior work showing robust topological protection in junctions with kink states, it is suggested that junctions are not required to achieve enhanced topological robustness. The formation of topological kink states at antiferromagnetic domain walls could be observed through conductance.

The understanding of proximity effects will be extended to all-epitaxial Iron/Magnesium Oxide/Vanadium (Fe/MgO/V) junctions. Collaborations with experimental groups are planned. While Fe/MgO is a building block for commercial spintronic applications, surprisingly, the normal-state conductance of Fe/MgO/V-based junctions is dominated by the orbital-symmetry-controlled spin orbit coupling rather than by the insulating MgO barrier. These peculiar manifestations appear to be related to the remarkable superconducting manifestation of the shot noise, the consequence of charge quantization, orders of magnitude larger than theoretically expected possible. Preliminary results suggest that V, as the parent conventional spin-singlet superconductor, leads to the proximity-induced spin-triplet superconductivity in Fe that appears independent of the parent V. A theoretical framework will be developed to explain how proximity effects could transform a single superconductor to act as a Josephson junction with two independent superconductors, where giant shot noise was previously observed. The aim is to establish the method of shot noise spectroscopy as a versatile probe for materials design and emergent phenomena in various proximity effects.

The research in this project directly addresses two of the Department of Energy’s Grand Challenges: Controlling materials processes at the level of electrons and establishing unique properties of matter emerging from complex correlations of the electronic constituents.