Publications related to Nearly free electron model

Room-Temperature Quantum Optomechanics and Free-Electron Quantum Optics

Quantum optics studies how photons interact with other forms of matter, the understanding of which was crucial for the development of quantum mechanics as a whole. Starting from the photoelectric effect, the quantum property of light has led to the develop ...

EPFL2024

Hierarchy of quasisymmetries and degeneracies in the CoSi family of chiral crystal materials

Philip Johannes Walter Moll, Chunyu Guo, Yi-Chiang Sun

In materials, certain approximated symmetry operations can exist in a lower-order approximation of the effective model but are good enough to influence the physical responses of the system, and these approximated symmetries were recently dubbed "quasisymme ...

AMER PHYSICAL SOC2023

Resonant Inelastic X-Ray Scattering Study of Electron-Exciton Coupling in High-T-c Cuprates

Fabrizio Carbone, Thorsten Schmitt, Ivan Madan, Christophe Berthod, Francesco Barantani, Yi Tseng, Dirk Van der Marel

Explaining the mechanism of superconductivity in the high-T-c cuprates requires an understanding of what causes electrons to form Cooper pairs. Pairing can be mediated by phonons, the screened Coulomb force, spin or charge fluctuations, excitons, or by a c ...

American Physical Society2022

Cavity-mediated electron-photon pairs

Tobias Kippenberg, Rui Ning Wang, Zheru Qiu, Yujia Yang, Junqiu Liu, Arslan Sajid Raja, Guanhao Huang

Quantum information, communication, and sensing rely on the generation and control of quantum correlations in complementary degrees of freedom. Free electrons coupled to photonics promise novel hybrid quantum technologies, although single-particle correlat ...

American Association for the Advancement of Science2022

Ultrafast Transverse Modulation of Free Electrons by Interaction with Shaped Optical Fields

Fabrizio Carbone, Ivan Madan, Alexey Sapozhnik, Thomas La Grange, Phoebe Marie Tengdin, Giovanni Maria Vanacore, Ido Kaminer, Simone Gargiulo, Francesco Barantani, Veronica Leccese

Spatiotemporal electron-beam shaping is a bold frontier of electron microscopy. Over the past decade, shaping methods evolved from static phase plates to low-speed electrostatic and magnetostatic displays. Recently, a swift change of paradigm utilizing lig ...

AMER CHEMICAL SOC2022

Time- and Angle-Resolved Photoelectron Spectroscopy of Solar Materials

Serhii Polishchuk

Natural foundations defining the manner in which a solid material interacts with optical radiation are primarily encoded in the material's momentum-dependent band structure and the microscopic details of the electron-lattice interactions. An access to this ...

EPFL2021

Magnonic crystals with reconfigurable magnetic defects for spin-based microwave electronics

Korbinian Baumgärtl

Collective spin excitations can propagate in magnetically ordered materials in the form of waves. These so-called spin waves (SWs) or magnons are promising for low-power beyond-CMOS information processing, which does not rely anymore on the lossy movement ...

EPFL2021

Spatio-temporal shaping of a free-electron wave function via coherent light-electron interaction

Fabrizio Carbone, Ivan Madan, Giovanni Maria Vanacore

The past decade has witnessed a quantum revolution in the field of computation, communication and materials investigation. A similar revolution is also occurring for free-electron based techniques, where the classical treatment of a free electron as a poin ...

SPRINGERNATURE2020

Electrons leave the flatland: out-of-plane charge dynamics in layered materials

Edoardo Martino

The goal of this thesis is to explore the "neglected" third dimension of layered materials, by studying the interlayer charge dynamics through dc conductivity, optical spectroscopy and ab-initio calculations. This project was designed to respond to the gro ...

EPFL2020

Direct Observation of the Statics and Dynamics of Emergent Magnetic Monopoles in a Chiral Magnet

Henrik Moodysson Rønnow, Jonathan White

In the three-dimensional (3D) Heisenberg model, topological point defects known as spin hedgehogs behave as emergent magnetic monopoles, i.e., quantized sources and sinks of gauge fields that couple strongly to conduction electrons, and cause unconventiona ...

AMER PHYSICAL SOC2020

Dynamics of excited interlayer states in hexagonal boron nitride monolayers

Josef Andreas Schuler, Silvan Dino Marcos Roth

Hexagonal boron nitride () is the isoelectronic but insulating counterpart of graphene. Like graphene it can easily be grown as high-quality nanotubes or as single layers on metal surfaces. Both materials can be exfoliated or transferred after single-layer ...

2020

Nanoscale imaging of mobile carriers and trapped charges in delta doped silicon p-n junctions

Gabriel Aeppli

Broadband electrostatic force microscopy can be used to non-destructively image n-type and p-type dopant layers in silicon devices with a lateral resolution of 10 nm and a vertical resolution of 0.5 nm. ...

NATURE PUBLISHING GROUP2020

Controlling free electrons with optical whispering-gallery modes

Tobias Kippenberg

Free-electron beams are versatile probes of microscopic structure and composition(1,2), and have revolutionized atomic-scale imaging in several fields, from solid-state physics to structural biology(3). Over the past decade, the manipulation and interactio ...

NATURE PUBLISHING GROUP2020

Evidence for biquadratic exchange in the quasi-two-dimensional antiferromagnet FePS3

Diane Virginie Marie Lançon

FePS3 is a van der Waals compound with a honeycomb lattice that is a good example of a two-dimensional antiferromagnet with Ising-like anisotropy. Neutron spectroscopy data from FePS3 were previously analyzed using a straightforward Heisenberg Hamiltonian ...

AMER INST PHYSICS2020

Picture of the wet electron: a localized transient state in liquid water

Alfredo Pasquarello, Francesco Ambrosio, Michele Pizzochero

A transient state of the excess electron in liquid water preceding the development of the solvation shell, the so-called wet electron, has been invoked to explain spectroscopic observations, but its binding energy and atomic structure have remained highly ...

2019

Exploring the Kondo Effect of an Extended Impurity with Chains of Co Adatoms in a Magnetic Field

Frédéric Mila

Motivated by recent STM experiments, we explore the magnetic field induced Kondo effect that takes place at symmetry protected level crossings in finite Co adatom chains. We argue that the effective two-level system realized at a level crossing acts as an ...

2019

Fast and ultrafast electron microscopies for skyrmions and plasmonics

Gabriele Berruto

In recent years, topology gained a central role in physics. We learnt that energetics could be often explained better by classes of objects defined by having qualitative differences. In today's jargon, we say they are topologically distinct. The process of ...

EPFL2019

Surface tension and viscosity of liquid Pd43Cu27Ni10P20 measured in a levitation device under microgravity

Roland Logé, Antonia Neels, Alex Dommann

Here we present measurements of surface tension and viscosity of the bulk glass-forming alloy Pd43Cu27Ni10P20 performed during containerless processing under reduced gravity. We applied the oscillating drop method in an electromagnetic levitation facility ...

Springer2019

Magnetoresistance from Fermi surface topology

Oleg Yazyev, Quansheng Wu, Shengnan Zhang, Yizhu Liu

Extremely large nonsaturating magnetoresistance has recently been reported for a large number of both topologically trivial and nontrivial materials. Different mechanisms have been proposed to explain the observed magnetotransport properties, yet without a ...

2019

Attosecond coherent control of free-electron wave functions using semi-infinite light fields

Fabrizio Carbone, Giovanni Maria Vanacore, Ivan Madan, Enrico Pomarico, Gabriele Berruto, Ido Kaminer, Brett Eugene Barwick

Light–electron interaction is the seminal ingredient in free-electron lasers and dynamical investigation of matter. Pushing the coherent control of electrons by light to the attosecond timescale and below would enable unprecedented applications in quantum ...

Nature Research2018