Publications

Order by: publication date number of citations

• Exclusion process subject to conformational size changes

  Yvan Rousset, Luca Ciandrini, Norbert Kern

  SciPost Phys. 6, 077 (2019) · published 26 June 2019 | Toggle abstract · pdf

  We introduce a model for stochastic transport on a one-dimensional substrate with particles assuming different conformations during their stepping cycles. These conformations correspond to different footprints on the substrate: in order to advance, particles are subject to successive contraction and expansion steps with different characteristic rates. We thus extend the paradigmatic exclusion process, provide predictions for all regimes of these rates that are in excellent agreement with simulations, and show that the current-density relation may be affected considerably. Symmetries are discussed, and exploited. We discuss our results in the context of molecular motors, confronting a hand-over-hand and an inchworm stepping mechanism, as well as for ribosomes.

• Tchavdar Dimitrov Palev - In memoriam

  N. I. Stoilova

  SciPost Phys. Proc. 14, 011 (2023) · published 23 November 2023 | Toggle abstract · pdf

  Tchavdar Dimitrov Palev – In memoriam

• One-dimensional Fermi polaron after a kick: Two-sided singularity of the momentum distribution, Bragg reflection and other exact results

  Oleksandr Gamayun, Oleg Lychkovskiy

  SciPost Phys. 17, 063 (2024) · published 23 August 2024 | Toggle abstract · pdf

  A mobile impurity particle immersed in a quantum fluid forms a polaron - a quasiparticle consisting of the impurity and a local disturbance of the fluid around it. We ask what happens to a one-dimensional polaron after a kick, i.e. an abrupt application of a force that instantly delivers a finite impulse to the impurity. In the framework of an integrable model describing an impurity in a one-dimensional gas of fermions or hard-core bosons, we calculate the distribution of the polaron momentum established when the post-kick relaxation is over. A remarkable feature of this distribution is a two-sided power-law singularity. It emerges due to one of two processes. In the first process, the whole impulse is transferred to the polaron, without creating phonon-like excitations of the fluid. In the second process, the impulse is shared between the polaron and the center-of-mass motion of the fluid, again without creating any fluid excitations. The latter process is, in fact, a Bragg reflection at the edge of the emergent Brillouin zone. We carefully analyze the conditions for each of the two processes. The asymptotic form of the distribution in the vicinity of the singularity is derived.

• A non-unitary bulk-boundary correspondence: Non-unitary Haagerup RCFTs from S-fold SCFTs

  Dongmin Gang, Dongyeob Kim, Sungjay Lee

  SciPost Phys. 17, 064 (2024) · published 23 August 2024 | Toggle abstract · pdf

  We introduce a novel class of two-dimensional non-unitary rational conformal field theories (RCFTs) whose modular data are identical to the generalized Haagerup-Izumi modular data. Via the bulk-boundary correspondence, they are related to the three-dimensional non-unitary Haagerup topological field theories, recently constructed by a topological twisting of three-dimensional $\mathcal{N}=4$ rank-zero superconformal field theories (SCFTs), called S-fold SCFTs. We propose that, up to the overall factors, the half-indices of the rank-zero SCFTs give the explicit Nahm representation of four conformal characters of the RCFTs including the vacuum character. Using the theory of Bantay-Gannon, we can successfully complete them into the full admissible conformal characters of the RCFTs.

• Physics motivation and detector upgrades for the new era of the ATLAS experiment

  Jason Nielsen

  SciPost Phys. Proc. 8, 126 (2022) · published 13 July 2022 | Toggle abstract · pdf

  The ATLAS experiment at CERN’s Large Hadron Collider (LHC) will be upgraded in two stages to prepare first for the Run 3 data-taking campaign, during which the integrated luminosity will roughly double, and then for the High-Luminosity LHC program with an ultimate integrated luminosity of up to 4 ab-1. These upgrades and high-statistics datasets will allow ATLAS to perform searches and precision measurements to constrain the Standard Model in yet-unexplored phase spaces and in the Higgs sector. This contribution summarizes the ATLAS detector upgrades and selected physics prospects for Run 3 and the HL-LHC.

• Forward trijet production and saturation

  Andreas van Hameren

  SciPost Phys. Proc. 8, 022 (2022) · published 11 July 2022 | Toggle abstract · pdf

  We present a multi-parton extension of the so-called small-$\boldsymbol{x}$ Improved Transverse Momentum Dependent (ITMD) factorization for hadroproduction of three or more jets in the forward rapidity region, allowing to study gluon saturation using such processes.

• A quantum register using collective excitations in a Bose-Einstein condensate

  Elisha Haber, Zekai Chen, Nicholas P. Bigelow

  SciPost Phys. 15, 188 (2023) · published 8 November 2023 | Toggle abstract · pdf

  A qubit made up of an ensemble of atoms is attractive due to its resistance to atom losses. In this work, we consider an experimentally feasible protocol to coherently load a spin-dependent optical lattice from a spatially overlapping Bose-Einstein condensate. Identifying each lattice site as a qubit, with an empty or filled site as the qubit basis, we discuss how high-fidelity single-qubit operations, two-qubit gates between arbitrary pairs of qubits, and nondestructive measurements could be performed. In this setup, the effect of atom losses has been mitigated, the atoms never need to be removed from the ground state manifold, and separate storage and computational bases for the qubits are not required, all of which can be significant sources of decoherence in many other types of atomic qubits.

• WG2 Summary: Small-x, Diffraction and Vector Mesons

  Tolga Altinoluk, Marta Luszczak, Daniel Tapia Takaki

  SciPost Phys. Proc. 8, 110 (2022) · published 13 July 2022 | Toggle abstract · pdf

  Here we briefly summarize the contributions to Working Group 2: Small-x, Diffraction and Vector Mesons, at the DIS2021 Workshop.

• Mean-field theory of first-order quantum superconductor-insulator transition

  Igor Poboiko, Mikhail Feigel'man

  SciPost Phys. 17, 066 (2024) · published 23 August 2024 | Toggle abstract · pdf

  Recent experimental studies on strongly disordered indium oxide films have revealed an unusual first-order quantum phase transition between the superconducting and insulating states (SIT). This transition is characterized by a discontinuous jump from non-zero to zero values of superfluid stiffness at the critical point, contradicting the conventional "scaling scenario" typically associated with SIT. In this paper, we present a theoretical framework for understanding this first-order transition. Our approach is based on the concept of competition between two fundamentally distinct ground states that arise from electron pairs initially localized by strong disorder: the superconducting state and the Coulomb glass insulator. These ground states are distinguished by two crucially different order parameters, suggesting a natural expectation of a discontinuous transition between them at $T=0$. This transition occurs when the magnitudes of the superconducting gap $\Delta$ and the Coulomb gap $E_C$ become comparable. Additionally, we extend our analysis to low non-zero temperatures and provide a mean-field "phase diagram" in the plane of $(T/\Delta,E_C/\Delta)$. Our results reveal the existence of a natural upper bound for the kinetic inductance of strongly disordered superconductors.

• The Soft Anomalous Dimension at four loops in the Regge Limit

  Niamh Maher, Giulio Falcioni, Einan Gardi, Calum Milloy, Leonardo Vernazza

  SciPost Phys. Proc. 7, 013 (2022) · published 20 June 2022 | Toggle abstract · pdf

  The soft anomalous dimension governs the infrared divergences of scattering amplitudes in general kinematics to all orders in perturbation theory. By comparing the recent Regge-limit results for $2\to2$ scattering (through Next-to-Next-to-Leading Logarithms) in full colour to a general form for the soft anomalous dimension at four loops we derive powerful constraints on its kinematic dependence, opening the way for a bootstrap-based determination.