Publications

Order by: publication date number of citations

• Massive fields and Wilson spools in JT gravity

  Jackson R. Fliss

  SciPost Phys. 19, 065 (2025) · published 3 September 2025 | Toggle abstract · pdf

  We give a prescription for minimally coupling massive matter to JT gravity with either sign of cosmological constant directly in its formulation as a topological BF theory. This coupling takes the form of a 'Wilson spool,' originally introduced in the context of three-dimensional gravity. The Wilson spool expresses the exact one-loop partition function as the integral over a Wilson loop operator. We construct the spool by considering the partition function of a massive scalar field on Euclidean dS$_2$ and on Euclidean AdS$_2$. We discuss its extension to other geometries (including the 'trumpet' and conical defect geometries) and its relation to the three-dimensional spool through dimensional reduction.

  1 citation

• Low-temperature electron mobility in doped semiconductors with high dielectric constant

  Khachatur G. Nazaryan, Mikhail Feigel'man

  SciPost Phys. 14, 046 (2023) · published 23 March 2023 | Toggle abstract · pdf

  We propose and study theoretically a new mechanism of electron-impurity scattering in doped seminconductors with large dielectric constant. It is based upon the idea of vector character of deformations caused in the crystalline lattice by any point defects siting asymmetrically in the unit cell. In result, local lattice compression due to the elastic deformations decay as $1/r^2$ with distance from impurity. Electron scattering (due to standard deformation potential) on such defects leads to low-temperature mobility $\mu(n)$ scaling with electron density $n$ of the form $\mu(n) \propto n^{-2/3}$ that is close to experimental observations on a number of relevant materials.

  1 citation

• Doping lattice non-Abelian quantum Hall states

  Zhengyan Darius Shi, Carolyn Zhang, Senthil Todadri

  SciPost Phys. 19, 150 (2025) · published 9 December 2025 | Toggle abstract · pdf

  We study quantum phases of a fluid of mobile charged non-Abelian anyons, which arise upon doping the lattice Moore-Read quantum Hall state at lattice filling $\nu = 1/2$ and its generalizations to the Read-Rezayi ($RR_k$) sequence at $\nu = k/(k+2)$. In contrast to their Abelian counterparts, non-Abelian anyons present unique challenges due to their non-invertible fusion rules and non-Abelian braiding structures. We address these challenges using a Chern-Simons-Ginzburg-Landau (CSGL) framework that incorporates the crucial effect of energy splitting between different anyon fusion channels at nonzero dopant density. For the Moore-Read state, we show that doping the charge $e/4$ non-abelion naturally leads to a fully gapped charge-$2$ superconductor without any coexisting topological order. The chiral central charge of the superconductor depends on details of the interactions determining the splitting of anyon fusion channels. For general $RR_k$ states, our analysis of states obtained by doping the basic non-abelion $a_0$ with charge $e/(k+2)$ reveals a striking even/odd pattern in the Read-Rezayi index $k$. We develop a general physical picture for anyon-driven superconductivity based on charge-flux unbinding, and show how it relates to the CSGL description of doped Abelian quantum Hall states. Finally, as a bonus, we use the CSGL formalism to describe transitions between the $RR_k$ state and a trivial period-$(k+2)$ CDW insulator at fixed filling, driven by the gap closure of the fundamental non-Abelian anyon $a_0$. Notably, for $k=2$, this predicts a period-4 CDW neighboring the Moore-Read state at half-filling, offering a potential explanation of recent numerical observations in models of twisted MoTe$_2$.

  1 citation

• Floquet fractional Chern insulators and competing phases in twisted bilayer graphene

  Peng-Sheng Hu, Yi-Han Zhou, Zhao Liu

  SciPost Phys. 15, 148 (2023) · published 10 October 2023 | Toggle abstract · pdf

  We study the many-body physics in twisted bilayer graphene coupled to periodic driving of a circularly polarized light when electron-electron interactions are taken into account. In the limit of high driving frequency $\Omega$, we use Floquet theory to formulate the system by an effective static Hamiltonian truncated to the order of $\Omega^{-2}$, which consists of a single-electron part and the screened Coulomb interaction. We numerically simulate this effective Hamiltonian by extensive exact diagonalization in the parameter space spanned by the twist angle and the driving strength. Remarkably, in a wide region of the parameter space, we identify Floquet fractional Chern insulator states in the partially filled Floquet valence bands. We characterize these topologically ordered states by ground-state degeneracy, spectral flow, and entanglement spectrum. In regions of the parameter space where fractional Chern insulator states are absent, we find topologically trivial charge density waves and band-dispersion-induced Fermi liquids which strongly compete with fractional Chern insulator states.

  1 citation

• Codebase release 1.0 for GRIFFIN

  Lisong Chen, Ayres Freitas

  SciPost Phys. Codebases 18-r1.0 (2023) · published 10 October 2023 | Toggle abstract · src

  This paper describes a modular framework for the description of electroweak scattering and decay processes, including but not limited to Z-resonance physics. The framework consistently combines a complex-pole expansion near an s-channel resonance with a regular fixed-order perturbative description away from the resonance in a manifestly gauge-invariant scheme. Leading vertex correction contributions are encapsulated in form factors that can be predicted or treated as numerical fit parameters. This framework has been implemented in the publicly available object-oriented C++ library GRIFFIN. Version 1.0 of this library provides Standard Model predictions for the IR-subtracted matrix elements for the process $f\bar{f} \to f'\bar{f}'$ with full NNLO and leading higher-order contributions on the Z-resonance, and with NLO corrections off-resonance. The library can straightforwardly be extended to include higher-order corrections, should they become available, or predictions for new physics models. It can be interfaced with Monte-Carlo programs to account for QED and QCD initial-state and final-state radiation.

  1 citation

• Photon pumping, photodissociation and dissipation at interplay for the fluorescence of a molecule in a cavity

  Megha Gopalakrishna, Emil Viñas Boström, Claudio Verdozzi

  SciPost Phys. 15, 138 (2023) · published 5 October 2023 | Toggle abstract · pdf

  We introduce a model description of a diatomic molecule in an optical cavity, with pump and fluorescent fields, and electron and nuclear motion are treated on equal footing and exactly. The model accounts for several optical response temporal scenarios: A Mollow spectrum hindered by electron correlations, a competition of harmonic generation and molecular dissociation, a dependence of fluorescence on photon pumping rate and dissipation. It is thus a general and flexible template for insight into experiments where quantum photon confinement, leakage, nuclear motion and electronic correlations are at interplay.

  1 citation

• Muonium reaction in MgO: A showcase for the final steps of ion implantation

  Rui C. Vilão, Ali Roonkiani, Apostolos G. Marinopoulos, Helena V. Alberto, João M. Gil, Ricardo B. L. Vieira, Robert Scheuermann, Alois Weidinger

  SciPost Phys. Core 8, 056 (2025) · published 26 August 2025 | Toggle abstract · pdf

  We present an in-depth investigation of the implantation of positive muons in magnesium oxide (MgO). Muonium, the positive muon plus an electron is an analogue of the hydrogen atom. This study describes the final stage of the implantation process, from muon diffusion over the potential barrier and the stopping by an inelastic reaction to the final embedding of the muon into the lattice structure. A special aspect is a relatively long-lived intermediate configuration which lasts for several hundred nanoseconds or more and is accessible to muon spin spectroscopy. The model presented here provides a framework for the analysis of the general case of ion implantation.

  1 citation

• Twisted gauging and topological sectors in (2+1)d Abelian lattice gauge theories

  Bram Vancraeynest-De Cuiper, Clement Delcamp

  SciPost Phys. 19, 054 (2025) · published 22 August 2025 | Toggle abstract · pdf

  Given a two-dimensional quantum lattice model with an Abelian gauge theory interpretation, we investigate a duality operation that amounts to gauging its invertible 1-form symmetry, followed by gauging the resulting 0-form symmetry in a twisted way via a choice of discrete torsion. Using tensor networks, we introduce explicit lattice realisations of the so-called condensation defects, which are obtained by gauging the 1-form symmetry along submanifolds of spacetime, and employ the same calculus to realise the duality operators. By leveraging these tensor network operators, we compute the non-trivial interplay between symmetry-twisted boundary conditions and charge sectors under the duality operation, enabling us to construct isometries relating the dual Hamiltonians. Whenever a lattice gauge theory is left invariant under the duality operation, we explore the possibility of promoting the self-duality to an internal symmetry. We argue that this results in a symmetry structure that encodes the 2-representations of a 2-group.

  1 citation

• EUSO-SPB2: A sub-orbital cosmic ray and neutrino multi-messenger pathfinder observatory

  Austin Cummings, Johannes Eser, George Filippatos, Angela V. Olinto, Tonia M. Venters, Lawrence Wiencke for the JEM-EUSO collaboration

  SciPost Phys. Proc. 13, 038 (2023) · published 29 September 2023 | Toggle abstract · pdf

  The next generation of ultra-high energy cosmic ray (UHECR) and very-high energy neutrino observatories will address the challenge of the extremely low fluxes of these particles at the highest energies. EUSO-SPB2 (Extreme Universe Space Observatory on a Super Pressure Balloon 2) is designed to prepare space missions to address this challenge. EUSO-SPB2 is equipped with 2 telescopes: the Fluorescence Telescope, which will point downwards and measure fluorescence emission from UHECR air showers with an energy above 2 EeV, and the Cherenkov Telescope (CT), which will point towards the Earth's limb and measure direct Cherenkov emission from cosmic rays with energies above 1 PeV verifying the technique. Pointed below the limb, the CT will search for Cherenkov emission produced by neutrino-sourced tau-lepton decays above 10 PeV energies and study backgrounds for such events. The EUSO-SPB2 mission will provide pioneering observations and technical milestones on the path towards a space-based multi-messenger observatory.

  1 citation

• Lattice random walks and quantum A-period conjecture

  Li Gan

  SciPost Phys. 19, 053 (2025) · published 21 August 2025 | Toggle abstract · pdf

  We derive explicit closed-form expressions for the generating function $C_N(A)$, which enumerates classical closed random walks on square and triangular lattices with $N$ steps and a signed area $A$, characterized by the number of moves in each hopping direction. This enumeration problem is mapped to the trace of powers of anisotropic Hofstadter-like Hamiltonian and is connected to the cluster coefficients of exclusion particles: Exclusion strength parameter $g = 2$ for square lattice walks, and a mixture of $g = 1$ and $g = 2$ for triangular lattice walks. By leveraging the intrinsic link between the Hofstadter model and high energy physics, we propose a conjecture connecting the above signed area enumeration $C_N(A)$ in statistical mechanics to the quantum A-period of associated toric Calabi–Yau threefold in topological string theory: Square lattice walks correspond to local $\mathbb{F}_0$ geometry, while triangular lattice walks are associated with local $\mathcal{B}_3$.

  1 citation