# Annica Black-Schaffer

Professor at Department of Physics and Astronomy; Materials Theory

- Mobile phone:
- +46 76 795 06 49
- E-mail:
- annica.black-schaffer@physics.uu.se
- Visiting address:
- ÅngströmlaboratorLägerhyddsvägen 1

SE-75237 Uppsala

Sweden - Postal address:
- Box 516

751 20 UPPSALA

Professor at Department of Physics and Astronomy; Materials Theory; Kvantmateriens teori

- Mobile phone:
- +46 76 795 06 49
- E-mail:
- annica.black-schaffer@physics.uu.se
- Visiting address:
- ÅngströmlaboratorLägerhyddsvägen 1

SE-75237 Uppsala

Sweden - Postal address:
- Box 516

751 20 UPPSALA

More information is available to staff who log in.

## Short presentation

I am a professor and head of the Quantum Matter Theory research program at the Department of Physics and Astronomy. The work in my research group is mainly focused on the mechanisms and properties of unconventional and topological superconductivity. We use detailed models to study superconductivity in many different novel materials and superconducting hybrid structures.

For more information, please see our group webpage.

## Biography

I am a Full Professor in Quantum Matter Theory at the Department of Physics and Astronomy. I received my Ph.D. in condensed matter theory in 2009 from Stanford University. I then spent 1.5 years as a postdoctoral fellow at the Nordic Institute for Theoretical Physics, NORDITA, in Stockholm, before moving to Uppsala. My research interests primarily spans superconductivity, topological states of matter, and strongly correlated electron systems.

The research in my group is currently mainly focused on the mechanisms and properties of unconventional and topological superconductors. We mostly use low-energy effective models to study the properties of the superconducting state in many different novel materials. One of our interests is topological superconductors with Majorana fermions. Approximately one can say that a Majorana fermion is half an electron, or more accurately, in a system with Majorana fermions the wave function of an electron has split up into two separate parts. We are also working on unconventional superconductivity in honeycomb-like materials, such as graphene, which are also prone to host topological superconductivity. Another larger area of current interest is expanding the mechanisms and materials for odd-frequency superconductivity, especially in spin-orbit coupled materials and multiband superconductors.

Our work is supported by external grants from the European Research Council (ERC Starting Grant 2017, ERC Consolidator Grant 2022), the Swedish Research Council (VR Consolidator Grant 2022, VR project and starting grants), and the Knut and Alice Wallenberg Foundation (Wallenberg Scholar 2024, Wallenberg Academy Fellow 2014 with prolongation 2019, and Wallenberg project grants). Previous support from the Göran Gustafsson Foundation, the Swedish Foundation for Strategic Research, the L’Oréal-UNESCO For Women in Science Prize Sweden, the Wenner-Gren Foundations, and the Carl Trygger Foundation is also gratefully acknowledged.

For more information, please see our group webpage.

## Publications

### Recent publications

- Nonlocality of Majorana bound states revealed by electron waiting times in a topological Andreev interferometer (2024)
- Distinct quasiparticle interference patterns for surface impurity scattering on various Weyl semimetals (2024)
- Topological superconductivity enhanced by exceptional points (2023)
- Mitigating disorder-induced zero-energy states in weakly coupled superconductor-semiconductor hybrid systems (2023)
- Superconductivity and magnetism in the surface states of ABC-stacked multilayer graphene (2023)

### All publications

#### Articles

- Nonlocality of Majorana bound states revealed by electron waiting times in a topological Andreev interferometer (2024)
- Distinct quasiparticle interference patterns for surface impurity scattering on various Weyl semimetals (2024)
- Topological superconductivity enhanced by exceptional points (2023)
- Mitigating disorder-induced zero-energy states in weakly coupled superconductor-semiconductor hybrid systems (2023)
- Superconductivity and magnetism in the surface states of ABC-stacked multilayer graphene (2023)
- Zero-frequency supercurrent susceptibility signatures of trivial and topological zero-energy states in nanowire junctions (2023)
- Defect-induced band restructuring and length scales in twisted bilayer graphene (2023)
- Bulk Bogoliubov Fermi arcs in non-Hermitian superconducting systems (2023)
- Superconductivity in monolayer and few-layer graphene. II (2023)
- Fano Resonances for Tilted Linear and Quadratic Band Touching Dispersions in a Harmonically Driven Potential Well (2023)
- Coreless vortices as direct signature of chiral
*d*-wave superconductivity (2023) - Enhanced chiral edge currents and orbital magnetic moment in chiral
*d*-wave superconductors from mesoscopic finite-size effects (2023) - Robust and tunable coreless vortices and fractional vortices in chiral
*d*-wave superconductors (2023) - Detrimental effects of disorder in two-dimensional time-reversal invariant topological superconductors (2023)
- Superconductivity in monolayer and few-layer graphene. III. Impurity-induced subgap states and quasiparticle interference patterns (2023)
- Superconductivity in monolayer and few-layer graphene (2023)
- Robust topological superconductivity in weakly coupled nanowire-superconductor hybrid structures (2022)
- Thermodefect voltage in graphene nanoribbon junctions (2022)
- Exceptional odd-frequency pairing in non-Hermitian superconducting systems (2022)
- Phase-tunable electron transport assisted by odd-frequency Cooper pairs in topological Josephson junctions (2022)
- Quasiparticle Interference as a Direct Experimental Probe of Bulk Odd-Frequency Superconducting Pairing (2022)
- Interplay of finite-energy and finite-momentum superconducting pairing (2022)
- Disorder-robust phase crystal in high-temperature superconductors stabilized by strong correlations (2022)
- Superconducting quantum interference at the atomic scale (2022)
- Nematic superconductivity in magic-angle twisted bilayer graphene from atomistic modeling (2022)
- Superconducting pairing from repulsive interactions of fermions in a flat-band system (2022)
- Superconducting density of states and band structure at the surface of the candidate topological superconductor Au2Pb (2022)
- Distinguishing trivial and topological zero-energy states in long nanowire junctions (2021)
- Floquet engineering bulk odd-frequency superconducting pairs (2021)
- Odd-frequency pair density wave correlations in underdoped cuprates (2021)
- Superconductivity in spin-3/2 systems (2021)
- Disorder-robust
*p*-wave pairing with odd-frequency dependence in normal metal-conventional superconductor junctions (2021) - Efficient numerical method for evaluating normal and anomalous time-domain equilibrium Green's functions in inhomogeneous systems (2021)
- Diamagnetic and paramagnetic Meissner effect from odd-frequency pairing in multiorbital superconductors (2021)
- Dynamic Quantum Matter (2020)
- Odd-frequency superconducting pairing in one-dimensional systems (2020)
- Thermoelectricity carried by proximity-induced odd-frequency pairing in ferromagnet/superconductor junctions (2020)
- Finite bulk Josephson currents and chirality blockade removal from interorbital pairing in magnetic Weyl semimetals (2020)
- Suppression of odd-frequency pairing by phase disorder in a nanowire coupled to Majorana zero modes (2020)
- Identification of topological superconductivity in magnetic impurity systems using bulk spin polarization (2020)
- Spontaneous ferromagnetism and finite surface energy gap in the topological insulator Bi2Se3 from surface Bi-se antisite defects (2020)
- Large Josephson current in Weyl nodal loop semimetals due to odd-frequency superconductivity (2020)
- Odd-frequency superconductivity and Meissner effect in the doped topological insulator Bi2Se3 (2020)
- Highly tunable magnetic coupling in ultrathin topological insulator films due to impurity resonances (2020)
- Bulk odd-frequency pairing in the superconducting Su-Schrieffer-Heeger model (2020)
- Enhanced Majorana bound states in magnetic chains on superconducting topological insulator edges (2020)
- The Role of Odd-Frequency Pairing in Multiband Superconductors (2020)
- Supercurrent Detection of Topologically Trivial Zero-Energy States in Nanowire Junctions (2019)
- Wilson loop approach to fragile topology of split elementary band representations and topological crystalline insulators with time-reversal symmetry (2019)
- Signature of odd-frequency equal-spin triplet pairing in the Josephson current on the surface of Weyl nodal loop semimetals (2019)
- Majorana bound states in magnetic impurity chains (2019)
- Impact of topology on the impurity effects in extended s-wave superconductors with spin-orbit coupling (2019)
- Gap oscillations and Majorana bound states in magnetic chains on superconducting honeycomb lattices (2019)
- Majorana bound state localization and energy oscillations for magnetic impurity chains on conventional superconductors (2019)
- Odd-frequency pairing in a superconductor coupled to two parallel nanowires (2019)
- Odd-frequency superconductivity induced by nonmagnetic impurities (2019)
- Odd-frequency superconducting pairing in Kitaev-based junctions (2019)
- Probing unconventional superconductivity in proximitized graphene by impurity scattering (2018)
- Probing chiral edge states in topological superconductors through spin-polarized local density of state measurements (2018)
- Solid-state Stern-Gerlach spin splitter for magnetic field sensing, spintronics, and quantum computing (2018)
- Tuning Majorana zero modes with temperature in pi-phase Josephson junctions (2018)
- Topological nodal superconducting phases and topological phase transition in the hyperhoneycomb lattice (2018)
- Odd-frequency superconducting pairing in junctions with Rashba spin-orbit coupling (2018)
- Finite length effect on supercurrents between trivial and topological superconductors (2018)
- Andreev spectrum and supercurrents in nanowire-based SNS junctions containing Majorana bound states (2018)
- Topological superconductivity in the extended Kitaev-Heisenberg model (2018)
- Odd-frequency pairing and Kerr effect in the heavy-fermion superconductor UPt3 (2018)
- Domain walls in a chiral d-wave superconductor on the honeycomb lattice (2017)
- Disorder robustness and protection of Majorana bound states in ferromagnetic chains on conventional superconductors (2017)
- Superconducting order parameter π-phase shift in magnetic impurity wires (2017)
- Global band topology of simple and double Dirac-point semimetals (2017)
- Odd-frequency superconducting pairing and subgap density of states at the edge of a two-dimensional topological insulator without magnetism (2017)
- Majorana splitting from critical currents in Josephson junctions (2017)
- Odd-Frequency Superconductivity in Sr2RuO4 Measured by Kerr Rotation (2017)
- Multiple odd-frequency superconducting states in buckled quantum spin Hall insulators with time-reversal symmetry (2017)
- Universal phase diagrams with superconducting domes for electronic flat bands (2017)
- Impurity bound states in fully gapped d-wave superconductors with subdominant order parameters (2017)
- Highly tunable time-reversal-invariant topological superconductivity in topological insulator thin films (2017)
- Granular superconductor in a honeycomb lattice as a realization of bosonic Dirac material (2016)
- Majorana fermions at odd junctions in a wire network of ferromagnetic impurities (2016)
- Magnon Dirac materials (2016)
- Quantum ground state control in superconductor-silicene structures (2016)
- From chiral d-wave to nodal line superconductivity in the harmonic honeycomb lattices (2016)
- Probing vortex Majorana fermions and topology in semiconductor/superconductor heterostructures (2015)
- Spin-polarized edge currents and Majorana fermions in one- and two-dimensional topological superconductors (2015)
- Filling of magnetic-impurity-induced gap in topological insulators by potential scattering (2015)
- Topological superconductivity in two dimensions with mixed chirality (2015)
- Experimentally observable signatures of odd-frequency pairing in multiband superconductors (2015)
- Currents Induced by Magnetic Impurities in Superconductors with Spin-Orbit Coupling (2015)
- Skyrmion spin texture in ferromagnetic semiconductor-superconductor heterostructures (2014)
- Chiral d-wave superconductivity in doped graphene (2014)
- Chiral d-wave superconductivity on the honeycomb lattice close to the Mott state (2014)
- Spontaneous gap generation on the surface of weakly interacting topological insulators using nonmagnetic impurities (2014)
- Engineered near-perfect backscattering on the surface of a topological insulator with nonmagnetic impurities (2014)
- Defects in the d+id-wave superconducting state in heavily doped graphene (2014)
- Unconventional proximity-induced superconductivity in bilayer systems (2014)
- Dirac materials (2014)
- Band inversion and the topological phase transition in (Pb,Sn)Se (2014)
- Vortex states and Majorana fermions in spin-orbit coupled semiconductor-superconductor hybrid structures (2013)
- Chiral d-wave superconducting state in the core of a doubly quantized s-wave vortex in graphene (2013)
- Odd-frequency superconducting pairing in multiband superconductors (2013)
- Proximity-induced unconventional superconductivity in topological insulators (2013)
- Model Evidence of a Superconducting State with a Full Energy Gap in Small Cuprate Islands (2013)
- Edge Properties and Majorana Fermions in the Proposed Chiral d-Wave Superconducting State of Doped Graphene (2012)
- Subsurface impurities and vacancies in a three-dimensional topological insulator (2012)
- Odd-frequency superconducting pairing in topological insulators (2012)
- Strong potential impurities on the surface of a topological insulator (2012)
- Majorana fermions in spin-orbit-coupled ferromagnetic Josephson junctions (2011)
- Topological nodal superconductivity arising from the extended Kitaev-Heisenberg interaction on the hyperhoneycomb lattice

#### Other

- Nematic superconductivity in magic-angle twisted bilayer graphene from atomistic modeling (2021)
- Efficient numerical method for evaluating normal and anomalous time-dependent equilibrium Green’s functions in inhomogeneous systems (2020)
- Disorder-robust $p$-wave pairing with odd frequency dependence in normal metal-conventional superconductor junctions (2020)