Domenico Di Sante

Office C004

Viale C. Berti Pichat 6/2

40127 Bologna, Italy

I am an Associate Professor at the University of Bologna. I earned a B.S. in physics at the University of L’Aquila in 2011 and a Ph.D. in physics in 2015. I subsequently was a postdoctoral fellow and young group leader at the Physics Department of the University of Würzburg (2016-2020), and a Marie Curie Research Fellow at the Center for Computational Quantum Physics of the Flatiron Institute in New York (2021-2023).

My research is focused on the numerical quantum simulations of the electronic properties of interacting material systems, with emphasis on topology and spin-orbit driven phenomena. I was the principal investigator of an individual Marie Curie fellowship which aims at using machine learning applications in condensed matter problems.

selected publications

Flat band separation and robust spin Berry curvature in bilayer kagome metals

Domenico Di Sante, Chiara Bigi, Philipp Eck, and 16 more authors

Nature Physics Aug 2023

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Kagome materials have emerged as a setting for emergent electronic phenomena that encompass different aspects of symmetry and topology. It is debated whether the XV6Sn6 kagome family (where X is a rare-earth element), a recently discovered family of bilayer kagome metals, hosts a topologically non-trivial ground state resulting from the opening of spin–orbit coupling gaps. These states would carry a finite spin Berry curvature, and topological surface states. Here we investigate the spin and electronic structure of the XV6Sn6 kagome family. We obtain evidence for a finite spin Berry curvature contribution at the centre of the Brillouin zone, where the nearly flat band detaches from the dispersing Dirac band because of spin–orbit coupling. In addition, the spin Berry curvature is further investigated in the charge density wave regime of ScV6Sn6 and it is found to be robust against the onset of the temperature-driven ordered phase. Utilizing the sensitivity of angle-resolved photoemission spectroscopy to the spin and orbital angular momentum, our work unveils the spin Berry curvature of topological kagome metals and helps to define its spectroscopic fingerprint.
@article{di_sante_flat_2023, title = {Flat band separation and robust spin {Berry} curvature in bilayer kagome metals}, volume = {19}, copyright = {2023 The Author(s)}, issn = {1745-2481}, doi = {10.1038/s41567-023-02053-z}, language = {en}, number = {8}, journal = {Nature Physics}, author = {Di Sante, Domenico and Bigi, Chiara and Eck, Philipp and Enzner, Stefan and Consiglio, Armando and Pokharel, Ganesh and Carrara, Pietro and Orgiani, Pasquale and Polewczyk, Vincent and Fujii, Jun and King, Phil D. C. and Vobornik, Ivana and Rossi, Giorgio and Zeljkovic, Ilija and Wilson, Stephen D. and Thomale, Ronny and Sangiovanni, Giorgio and Panaccione, Giancarlo and Mazzola, Federico}, month = aug, year = {2023}, keywords = {Electronic properties and materials, Topological insulators}, pages = {1135--1142}, }
Observation of room temperature excitons in an atomically thin topological insulator

Marcin Syperek, Raul Stuehler, Armando Consiglio, and 10 more authors

Nature Communications Oct 2022

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Optical spectroscopy of ultimately thin materials has significantly enhanced our understanding of collective excitations in low-dimensional semiconductors. This is particularly reflected by the rich physics of excitons in atomically thin crystals which uniquely arises from the interplay of strong Coulomb correlation, spin-orbit coupling (SOC), and lattice geometry. Here we extend the field by reporting the observation of room temperature excitons in a material of non-trivial global topology. We study the fundamental optical excitation spectrum of a single layer of bismuth atoms epitaxially grown on a SiC substrate (hereafter bismuthene or Bi/SiC) which has been established as a large-gap, two-dimensional (2D) quantum spin Hall (QSH) insulator. Strongly developed optical resonances are observed to emerge around the direct gap at the K and K’ points of the Brillouin zone, indicating the formation of bound excitons with considerable oscillator strength. These experimental findings are corroborated, concerning both the character of the excitonic resonances as well as their energy scale, by ab-initio GW and Bethe-Salpeter equation calculations, confirming strong Coulomb interaction effects in these optical excitations. Our observations provide evidence of excitons in a 2D QSH insulator at room temperature, with excitonic and topological physics deriving from the very same electronic structure.
@article{syperek_observation_2022, title = {Observation of room temperature excitons in an atomically thin topological insulator}, volume = {13}, copyright = {2022 The Author(s)}, issn = {2041-1723}, doi = {10.1038/s41467-022-33822-8}, language = {en}, number = {1}, journal = {Nature Communications}, author = {Syperek, Marcin and Stuehler, Raul and Consiglio, Armando and Holewa, Pawel and Wyborski, Pawel and Dusanowski, Lukasz and Reis, Felix and Hoefling, Sven and Thomale, Ronny and Hanke, Werner and Claessen, Ralph and Di Sante, Domenico and Schneider, Christian}, month = oct, year = {2022}, note = {Number: 1 Publisher: Nature Publishing Group}, keywords = {Topological insulators, Two-dimensional materials}, pages = {6313}, }
Deep Learning the Functional Renormalization Group

Domenico Di Sante, Matija Medvidović, Alessandro Toschi, and 4 more authors

Physical Review Letters Sep 2022

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We perform a data-driven dimensionality reduction of the scale-dependent four-point vertex function characterizing the functional renormalization group (FRG) flow for the widely studied two-dimensional t−t′ Hubbard model on the square lattice. We demonstrate that a deep learning architecture based on a neural ordinary differential equation solver in a low-dimensional latent space efficiently learns the FRG dynamics that delineates the various magnetic and d-wave superconducting regimes of the Hubbard model. We further present a dynamic mode decomposition analysis that confirms that a small number of modes are indeed sufficient to capture the FRG dynamics. Our Letter demonstrates the possibility of using artificial intelligence to extract compact representations of the four-point vertex functions for correlated electrons, a goal of utmost importance for the success of cutting-edge quantum field theoretical methods for tackling the many-electron problem.
@article{di_sante_deep_2022, title = {Deep {Learning} the {Functional} {Renormalization} {Group}}, volume = {129}, doi = {10.1103/PhysRevLett.129.136402}, number = {13}, journal = {Physical Review Letters}, author = {Di Sante, Domenico and Medvidović, Matija and Toschi, Alessandro and Sangiovanni, Giorgio and Franchini, Cesare and Sengupta, Anirvan M. and Millis, Andrew J.}, month = sep, year = {2022}, note = {Publisher: American Physical Society}, pages = {136402}, }
Twofold van Hove singularity and origin of charge order in topological kagome superconductor CsV3Sb5

Mingu Kang, Shiang Fang, Jeong-Kyu Kim, and 14 more authors

Nature Physics Mar 2022

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The layered vanadium antimonides AV3Sb5 (A = K, Rb, Cs) are a recently discovered family of topological kagome metals that exhibit a range of strongly correlated electronic phases including charge order and superconductivity. However, it is not yet understood how the distinctive electronic structure of the kagome lattice is linked to the observed many-body phenomena. Here we combine angle-resolved photoemission spectroscopy and density functional theory to reveal multiple kagome-derived van Hove singularities (vHS) coexisting near the Fermi level of CsV3Sb5 and analyse their contribution to electronic symmetry breaking. The vHS are characterized by two distinct sublattice flavours (p-type and m-type), which originate, respectively, from their pure and mixed sublattice characters. These twofold vHS flavours of the kagome lattice critically determine the pairing symmetry and unconventional ground states emerging in the AV3Sb5 series. We establish that, among the multiple vHS in CsV3Sb5, the m-type vHS of the dxz/dyz kagome band and the p-type vHS of the dxy/dx2–y2 kagome band are located very close to the Fermi level, setting the stage for electronic symmetry breaking. The former band is characterized by pronounced Fermi surface nesting, while the latter exhibits a higher-order vHS. Our work reveals the essential role of kagome-derived vHS for the collective phenomena realized in the AV3Sb5 family.
@article{kang_twofold_2022, title = {Twofold van {Hove} singularity and origin of charge order in topological kagome superconductor {CsV3Sb5}}, volume = {18}, issn = {1745-2473, 1745-2481}, doi = {10.1038/s41567-021-01451-5}, language = {en}, number = {3}, journal = {Nature Physics}, author = {Kang, Mingu and Fang, Shiang and Kim, Jeong-Kyu and Ortiz, Brenden R. and Ryu, Sae Hee and Kim, Jimin and Yoo, Jonggyu and Sangiovanni, Giorgio and Di Sante, Domenico and Park, Byeong-Gyu and Jozwiak, Chris and Bostwick, Aaron and Rotenberg, Eli and Kaxiras, Efthimios and Wilson, Stephen D. and Park, Jae-Hoon and Comin, Riccardo}, month = mar, year = {2022}, pages = {301--308}, }
Triplet Superconductivity from Nonlocal Coulomb Repulsion in an Atomic Sn Layer Deposited onto a Si(111) Substrate

Sebastian Wolf, Domenico Di Sante, Tilman Schwemmer, and 2 more authors

Physical Review Letters Apr 2022

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Atomic layers deposited on semiconductor substrates introduce a platform for the realization of the extended electronic Hubbard model, where the consideration of electronic repulsion beyond the on-site term is paramount. Recently, the onset of superconductivity at 4.7 K has been reported in the hole-doped triangular lattice of tin atoms on a silicon substrate. Through renormalization group methods designed for weak and intermediate coupling, we investigate the nature of the superconducting instability in hole-doped Sn=Sið111Þ. We find that the extended Hubbard nature of interactions is crucial to yield triplet pairing, which is f-wave (p-wave) for moderate (higher) hole doping. In light of persisting challenges to tailor triplet pairing in an electronic material, our finding promises to pave unprecedented ways for engineering unconventional triplet superconductivity.
@article{wolf_triplet_2022, title = {Triplet {Superconductivity} from {Nonlocal} {Coulomb} {Repulsion} in an {Atomic} {Sn} {Layer} {Deposited} onto a {Si}(111) {Substrate}}, volume = {128}, issn = {0031-9007, 1079-7114}, doi = {10.1103/PhysRevLett.128.167002}, language = {en}, number = {16}, journal = {Physical Review Letters}, author = {Wolf, Sebastian and Di Sante, Domenico and Schwemmer, Tilman and Thomale, Ronny and Rachel, Stephan}, month = apr, year = {2022}, pages = {167002}, }
Nature of Unconventional Pairing in the Kagome Superconductors AV3Sb5 (A = K;Rb;Cs)

Xianxin Wu, Tilman Schwemmer, Tobias Müller, and 10 more authors

Physical Review Letters Oct 2021

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The recent discovery of AV3Sb5 (A=K,Rb,Cs) has uncovered an intriguing arena for exotic Fermi surface instabilities in a kagome metal. Among them, superconductivity is found in the vicinity of multiple van Hove singularities, exhibiting indications of unconventional pairing. We show that the sublattice interference mechanism is central to understanding the formation of superconductivity in a kagome metal. Starting from an appropriately chosen minimal tight-binding model with multiple van Hove singularities close to the Fermi level for AV3Sb5, we provide a random phase approximation analysis of superconducting instabilities. Nonlocal Coulomb repulsion, the sublattice profile of the van Hove bands, and the interaction strength turn out to be the crucial parameters to determine the preferred pairing symmetry. Implications for potentially topological surface states are discussed, along with a proposal for additional measurements to pin down the nature of superconductivity in AV3Sb5.
@article{wu_nature_2021, title = {Nature of {Unconventional} {Pairing} in the {Kagome} {Superconductors} {AV3Sb5} ({A} = {K};{Rb};{Cs})}, volume = {127}, doi = {10.1103/PhysRevLett.127.177001}, number = {17}, journal = {Physical Review Letters}, author = {Wu, Xianxin and Schwemmer, Tilman and Müller, Tobias and Consiglio, Armando and Sangiovanni, Giorgio and Di Sante, Domenico and Iqbal, Yasir and Hanke, Werner and Schnyder, Andreas P. and Denner, M. Michael and Fischer, Mark H. and Neupert, Titus and Thomale, Ronny}, month = oct, year = {2021}, note = {Publisher: American Physical Society}, pages = {177001}, }
Turbulent hydrodynamics in strongly correlated Kagome metals

Domenico Di Sante, Johanna Erdmenger, Martin Greiter, and 6 more authors

Nature Communications Aug 2020

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A current challenge in condensed matter physics is the realization of strongly correlated, viscous electron fluids. These fluids can be described by holography, that is, by mapping them onto a weakly curved gravitational theory via gauge/gravity duality. The canonical system considered for realizations has been graphene. In this work, we show that Kagome systems with electron fillings adjusted to the Dirac nodes provide a much more compelling platform for realizations of viscous electron fluids, including non-linear effects such as turbulence. In particular, we find that in Scandium Herbertsmithite, the fine-structure constant, which measures the effective Coulomb interaction, is enhanced by a factor of about 3.2 as compared to graphene. We employ holography to estimate the ratio of the shear viscosity over the entropy density in Sc-Herbertsmithite, and find it about three times smaller than in graphene. These findings put the turbulent flow regime described by holography within the reach of experiments. Viscous electron fluids are predicted in strongly correlated systems but remain challenging to realize. Here, the authors predict enhanced effective Coulomb interaction and reduced ratio of the shear viscosity over entropy density in a Kagome metal, inferring turbulent flow of viscous electron fluids.
@article{di_sante_turbulent_2020, title = {Turbulent hydrodynamics in strongly correlated {Kagome} metals}, volume = {11}, issn = {2041-1723}, doi = {10.1038/s41467-020-17663-x}, language = {English}, number = {1}, journal = {Nature Communications}, author = {Di Sante, Domenico and Erdmenger, Johanna and Greiter, Martin and Matthaiakakis, Ioannis and Meyer, Rene and Fernandez, David Rodriguez and Thomale, Ronny and van Loon, Erik and Wehling, Tim}, month = aug, year = {2020}, note = {Place: London Publisher: Nature Publishing Group WOS:000561071600002}, keywords = {coupling-constant dependence, electron, resistance, shear viscosity}, pages = {3997}, }