628 citations · 2.6k across the 33 of their papers we have counts for
34 papers
Parity-dependent double degeneracy and spectral statistics in the projected dice lattice
Koushik Swaminathan, Anouar Moustaj, Jose L. Lado +1
We investigate the spectral statistics of an interacting fermionic system derived by projecting the Hubbard interaction onto the two lowest-energy, degenerate flat bands of the dic…
Supersolid phase in two-dimensional soft-core bosons at finite temperature
Sebastiano Peotta, Gabriele Spada, Stefano Giorgini +2
The supersolid phase of soft-core bosons in two dimensions is investigated using the self-consistent Hartree-Fock and quantum Monte Carlo methods. An approximate phase diagram at f…
Coexistence of ergodic and non-ergodic behavior and level spacing statistics in a one-dimensional model of a flat band superconductor
Meri Teeriaho, Ville-Vertti Linho, Koushik Swaminathan +1
Motivated by recent studies of the projected dice lattice Hamiltonian [K. Swaminathan et al., Phys. Rev. Research 5, 043215 (2023)], we introduce the on-site/bond singlet (OBS) mod…
Superfluid weight in the isolated band limit within the generalized random phase approximation
Minh Tam, Sebastiano Peotta
The superfluid weight of a generic lattice model with attractive Hubbard interaction is computed analytically in the isolated band limit within the generalized random phase approxi…
Quantum geometry in superfluidity and superconductivity
Sebastiano Peotta, Kukka-Emilia Huhtinen, Päivi Törmä
We review the theoretical description of the role of quantum geometry in superfluidity and superconductivity of multiband systems, with focus on flat bands where quantum geometry i…
Signatures of many-body localization of quasiparticles in a flat band superconductor
Koushik Swaminathan, Poula Tadros, Sebastiano Peotta
We construct a class of exact eigenstates of the Hamiltonian obtained by projecting the Hubbard interaction term onto the flat band subspace of a generic lattice model. These exact…
Suppression of non-equilibrium quasiparticle transport in flat band superconductors
Ville A. J. Pyykkönen, Sebastiano Peotta, Päivi Törmä
We study non-equilibrium transport through a superconducting flat-band lattice in a two-terminal setup with the Schwinger-Keldysh method. We find that quasiparticle transport is su…
Superconductivity, generalized random phase approximation and linear scaling methods
Sebastiano Peotta
The superfluid weight is an important observable of superconducting materials since it is related to the London penetration depth of the Meissner effect. It can be computed from th…
Universal suppression of superfluid weight by disorder independent of quantum geometry and band dispersion
Alexander Lau, Sebastiano Peotta, Dmitry I. Pikulin +2
Motivated by the experimental progress in controlling the properties of the energy bands in superconductors, significant theoretical efforts have been devoted to study the effect o…
Dynamical quantum phase transitions in strongly correlated two-dimensional spin lattices following a quench
Fredrik Brange, Sebastiano Peotta, Christian Flindt +1
Dynamical quantum phase transitions are at the forefront of current efforts to understand quantum matter out of equilibrium. Except for a few exactly solvable models, predictions o…
Superfluidity and Quantum Geometry in Twisted Multilayer Systems
P. Törmä, S. Peotta, B. A. Bernevig
Designer 2D materials where the constituent layers are not aligned may result in band structures with dispersionless, "flat" bands. Twisted bilayer graphene has been found to show…
Flat band transport and Josephson effect through a finite-size sawtooth lattice
Ville A. J. Pyykkönen, Sebastiano Peotta, Philipp Fabritius +3
We study theoretically the transport through a finite-size sawtooth lattice coupled to two fermionic reservoirs kept in the superfluid state. We focus on the DC Josephson effect an…
Determination of dynamical quantum phase transitions in strongly correlated many-body systems using Loschmidt cumulants
Sebastiano Peotta, Fredrik Brange, Aydin Deger +2
Dynamical phase transitions extend the notion of criticality to non-stationary settings and are characterized by sudden changes in the macroscopic properties of time-evolving quant…
Flat band induced non-Fermi liquid behavior of multicomponent fermions
Pramod Kumar, Sebastiano Peotta, Yosuke Takasu +2
We investigate multicomponent fermions in a flat band and predict experimental signatures of non-Fermi liquid behavior. We use dynamical mean-field theory to obtain the density, do…
Quantum metric and effective mass of a two-body bound state in a flat band
Paivi Torma, Long Liang, Sebastiano Peotta
We consider two-body bound states in a flat band of a multiband system. The existence of pair dispersion predicts the possibility of breaking the degeneracy of the band and creatin…
Preformed pairs in flat Bloch bands
Murad Tovmasyan, Sebastiano Peotta, Long Liang +2
In a flat Bloch band the kinetic energy is quenched and single particles cannot propagate since they are localized due to destructive interference. Whether this remains true in the…
Spin-Imbalanced Pairing and Fermi Surface Deformation in Flat Bands
Kukka-Emilia Huhtinen, Marek Tylutki, Pramod Kumar +3
We study the attractive Hubbard model with spin imbalance on two lattices featuring a flat band: the Lieb and kagome lattices. We present mean-field phase diagrams featuring exotic…
Wave packet dynamics of Bogoliubov quasiparticles: quantum metric effects
Long Liang, Sebastiano Peotta, Ari Harju +1
We study the dynamics of the Bogoliubov wave packet in superconductors and calculate the supercurrent carried by the wave packet. We discover an anomalous contribution to the super…
Phase-dependent noise in Josephson junctions
Forrest Sheldon, Sebastiano Peotta, Massimiliano Di Ventra
In addition to the usual superconducting current, Josephson junctions (JJs) support a phase-dependent conductance related to the retardation effect of tunneling quasi-particles. Th…
Band geometry, Berry curvature and superfluid weight
Long Liang, Tuomas I. Vanhala, Sebastiano Peotta +3
We present a theory of the superfluid weight in multiband attractive Hubbard models within the Bardeen-Cooper-Schrieffer (BCS) mean field framework. We show how to separate the geo…
Effective theory and emergent symmetry in the flat bands of attractive Hubbard models
Murad Tovmasyan, Sebastiano Peotta, Päivi Törmä +1
In a partially filled flat Bloch band electrons do not have a well defined Fermi surface and hence the low-energy theory is not a Fermi liquid. Neverethless, under the influence of…
Geometric origin of superfluidity in the Lieb lattice flat band
Aleksi Julku, Sebastiano Peotta, Tuomas Vanhala +2
The ground state and transport properties of the Lieb lattice flat band in the presence of an attractive Hubbard interaction are considered. It is shown that the superfluid weight…
Dynamical symmetry and pair tunneling in a one-dimensional Bose gas colliding with a mobile impurity
Elmer V. H. Doggen, Sebastiano Peotta, Päivi Törmä +1
Using the time-dependent density matrix renormalization group (TDMRG) we theoretically study the collision of a one-dimensional gas of interacting bosons with an impurity trapped i…
Superfluidity in topologically nontrivial flat bands
Sebastiano Peotta, Päivi Törmä
Topological invariants built from the periodic Bloch functions characterize new phases of matter, such as topological insulators and topological superconductors. The most important…