Publications associées à Superfluid helium-4

Progress in the design and manufacturing of the EDIPO 2 cryostat

Pierluigi Bruzzone, Kamil Sedlák, Roberto Guarino, Evgeny Solodko

A major upgrade of the European DIPOle (EDIPO) test facility, which will allow the testing of superconducting samples both for fusion and for high-energy physics applications, is taking place at the Swiss Plasma Center. With a target background field of 15 ...

2023

Characterization of two electronic subsystems in cuprates through optical conductivity

Ana Akrap, Edoardo Martino, Neven Barisic

Understanding the physical properties of unconventional superconductors as well as of other correlated materials presents a formidable challenge. Their unusual evolution with doping, frequency, and temperature has frequently led to non-Fermi-liquid (non-FL ...

2023

Engineering SYK Interactions in Disordered Graphene Flakes under Realistic Experimental Conditions

Oleg Yazyev, Marta Agnieszka Brzezinska, Yifei Guan

We model interactions following the Sachdev-Ye-Kitaev (SYK) framework in disordered graphene flakes up to 300 000 atoms in size (-100 nm in diameter) subjected to an out-of-plane magnetic field B of 5-20 Tesla within the tight-binding formalism. We investi ...

AMER PHYSICAL SOC2023

Identifying Large Charge operators

Riccardo Rattazzi, Alexander Monin, Gil Badel

The Large Charge sector of Conformal Field Theory (CFT) can generically be described through a semiclassical expansion around a superfluid background. In this work, focussing on U(1) invariant Wilson-Fisher fixed points, we study the spectrum of spinning l ...

Springer Nature2023

Unveiling new quantum phases in the Shastry-Sutherland compound SrCu2(BO3)(2) up to the saturation magnetic field

Frédéric Mila

Under magnetic fields, quantum magnets often undergo exotic phase transitions with various kinds of order. The discovery of a sequence of fractional magnetization plateaus in the Shastry-Sutherland compound SrCu2(BO3)(2) has played a central role in the hi ...

Nature Portfolio2023

Many-body physics with strongly interacting fermions coupled to light

Victor Youri Helson

This thesis reports on the realization of the first experiments conducted with superfluid, strongly interacting Fermi gases of 6Li coupled to the light field of an optical cavity. In the scope of existing ultracold atomic platforms, this is the first time ...

EPFL2023

Density-wave ordering in a unitary Fermi gas with photon-mediated interactions

Jean-Philippe Brantut, Victor Youri Helson, Kevin Etienne Robert Roux, Hideki Konishi, Timo Zwettler, Elvia Colella

A density wave (DW) is a fundamental type of long-range order in quantum matter tied to self-organization into a crystalline structure. The interplay of DW order with superfluidity can lead to complex scenarios that pose a great challenge to theoretical an ...

NATURE PORTFOLIO2023

Hole-induced anomaly in the thermodynamic behavior of a one-dimensional Bose gas

Riccardo Rota

We reveal an intriguing anomaly in the temperature dependence of the specific heat of a one-dimensional Bose gas. The observed peak holds for arbitrary interaction and remembers a superfluid-to-normal phase transition in higher dimensions, but phase transi ...

SCIPOST FOUNDATION2022

Preliminary design of the pressure relief system of the EDIPO 2 helium vessel

Pierluigi Bruzzone, Kamil Sedlák, Roberto Guarino, Evgeny Solodko

The European Dipole (EDIPO) test facility is undergoing a major upgrade of its magnet assembly, which will provide ground for testing both fusion and high-energy physics superconducting samples at variable temperature and with a background field of 15 T. I ...

2022

Semiclassical methods in conformal field theories scrutinized by the epsilon-expansion

Gil Badel

Conformal Field Theories (CFTs) are crucial for our understanding of Quantum Field Theory (QFT). Because of their powerful symmetry properties, they play the role of signposts in the space of QFTs. Any method that gives us information about their structure ...

EPFL2022

Electromechanical investigations and quench experiments on sub-size HTS cables for high field EU-DEMO Central Solenoid

Ortensia Dicuonzo

The aim of this thesis is to investigate the mechanical and thermal behaviour of HTS coated conductor cables for EUROfusion DEMO magnets. One of the issue in large HTS magnets is the safety against a quench. A quench is a sudden thermal runway in which the ...

EPFL2022

How to improve the efficiency of a traditional dissolution dynamic nuclear polarization (dDNP) apparatus: Design and performance of a fluid path compatible dDNP/LOD-ESR probe

Andrea Capozzi, Jean-Noël Hyacinthe, Thanh Phong Kevin Lê

Dissolution Dynamic Nuclear Polarization (dDNP) was invented almost twenty years ago. Ever since, hardware advancement has observed 2 trends: the quest for DNP at higher field and, more recently, the development of cryogen free polarizers. Despite the DNP ...

Academic Press Inc - Elsevier Science2022

Directional detection of light dark matter from three-phonon events in superfluid He-4

Angelo Esposito

We present the analysis of a new signature for light dark matter detection with superfluid He-4: the emission of three phonons. We show that, in a region of mass below the MeV, the kinematics of this process can offer a way to reconstruct the dark matter i ...

American Physical Society2021

Emergent order in hydrodynamic spin lattices

Alexis Marie Frederic Goujon, John Bush

Macroscale analogues(1-3) of microscopic spin systems offer direct insights into fundamental physical principles, thereby advancing our understanding of synchronization phenomena(4) and informing the design of novel classes of chiral metamaterials(5-7). He ...

NATURE PORTFOLIO2021

Progress on the Design of the 15 T Magnet of the EDIPO Test Facility

Pierluigi Bruzzone, Kamil Sedlák, Roberto Guarino, Evgeny Solodko

EDIPO 2 (the upgraded EDIPO test facility) will provide a unique testbed for superconducting cables for fusion magnets,accelerators, and other applications. Compared to the previous magnet assembly, the magnetic field is enhanced from 12.35 T to 15 T, the ...

IEEE Institute of Electrical and Electronics Engineers2021

Scaling of the translational velocity of vortex rings behind conical objects

Karen Ann J Mulleners, Guillaume de Guyon-Crozier

Ring vortices are efficient at transporting fluid across long distances. They can be found in nature in various ways: they propel squids, inject blood in the heart, and entertain dolphins. These vortices are generally produced by ejecting a volume of fluid ...

2021

Emergence of Concentration Effects in the Variational Analysis of the N-Clock Model

Matthias Ruf, Matthias Benjamin Ruf

We investigate the relationship between the N-clock model (also known as planar Potts model or DOUBLE-STRUCK CAPITAL ZN-model) and the XY model (at zero temperature) through a Gamma-convergence analysis of a suitable rescaling of the energy as both the num ...

WILEY2022

Light Dark Matter and Superfluid He-4 from EFT

Angelo Esposito

We study the response of a He-4 detector to the interaction of sub-GeV dark matter using an effective field theory for the superfluid. We compute the lifetime of the phonon, which agrees with what known from standard techniques, hence providing an importan ...

IOP PUBLISHING LTD2020

Dark matter, dark photon and superfluid He-4 from effective field theory

Angelo Esposito, Emma Michèle Ginette Geoffray

We consider a model of sub-GeV dark matter whose interaction with the Standard Model is mediated by a new vector boson (the dark photon) which couples kinetically to the photon. We describe the possibility of constraining such a model using a superfluid He ...

2020

Angular Momentum in Rotating Superfluid Droplets

Christoph Bostedt, Camila Bacellar Cases Da Silveira

The angular momentum of rotating superfluid droplets originates from quantized vortices and capillary waves, the interplay between which remains to be uncovered. Here, the rotation of isolated submicrometer superfluid He-4 droplets is studied by ultrafast ...

AMER PHYSICAL SOC2020