Publications associées à On the optical properties of carbon nanotubes. Part I. A general formula for the dynamical optical conductivity

Automated all-functionals infrared and Raman spectra

Infrared and Raman spectroscopies are ubiquitous techniques employed in many experimental laboratories, thanks to their fast and non-destructive nature able to capture materials' features as spectroscopic fingerprints. Nevertheless, these measurements freq ...

Nature Portfolio2024

Functionalized Å-scale Pores in Graphene for Carbon Capture

Kuang-Jung Hsu

Single-layer graphene, hosting a high density of functionalized molecular-sieving atom-thick pores, is considered to be an excellent material for gas separation membranes. These functionalized atom-thick pores enable the shortest transport pathway across t ...

EPFL2024

Highly dispersed nanomaterials in polymer matrix via aerosol-jet-based multi-material 3D printing

Michael James Henry Smith

Polymer-based nanocomposites emerged in the 1960s as a groundbreaking approach to advanced materials. By incorporating robust, durable, and multifunctional nanomaterials into a polymer matrix, the performance of nanocomposites has significantly surpassed t ...

Elsevier2024

Tuning Pore Size in Graphene in the Angstrom Regime for Highly Selective Ion-Ion Separation

Kumar Varoon Agrawal, Luis Francisco Villalobos Vazquez de la Parra, Heng-Yu Chi, Wan-Chi Lee, Shaoxian Li, Kuang-Jung Hsu, Kangning Zhao, Yuyang Zhang

Zero-dimensional pores spanning only a few angstroms in size in two-dimensional materials such as graphene are some of the most promising systems for designing ion-ion selective membranes. However, the key challenge in the field is that so far a crack-free ...

Amer Chemical Soc2024

Nanolithography of the nanocorral structure of chemisorbed oxygen atoms on the graphitic lattice

Kumar Varoon Agrawal, Shaoxian Li

Controlled atomic patterning is an attractive tool to fine tune properties of graphitic lattice. Several O-functionalized derivatives of graphitic lattice have been widely studied, e.g., graphene oxide, reduced graphene oxide, and functionalized carbon nan ...

Pergamon-Elsevier Science Ltd2024

Electronic transport in graphene with out-of-plane disorder

Oleg Yazyev, Yifei Guan

Real-world samples of graphene often exhibit various types of out-of-plane disorder-ripples, wrinkles and folds-introduced at the stage of growth and transfer processes. These complex out-of-plane defects resulting from the interplay between self-adhesion ...

Nature Portfolio2024

Photoinduced Second-Order Nonlinearities in Centrosymmetric Media

Ozan Yakar

The interaction of light and matter enables nonlinear frequency conversion and the creation of coherent currents. The optical control of electric currents is of fundamental relevance and prominent research focus in the last decades. These photocurrents ena ...

EPFL2024

Electrochemical-repaired porous graphene membranes for precise ion-ion separation

Kumar Varoon Agrawal, Heng-Yu Chi, Kuang-Jung Hsu, Kangning Zhao, Shuqing Song, Zongyao Zhou

The preparation of atom-thick porous lattice hosting & Aring;-scale pores is attractive to achieve a large ion-ion selectivity in combination with a large ion flux. Graphene film is an ideal selective layer for this if high-precision pores can be incorpora ...

Nature Portfolio2024

Polarization-enhanced GaN Schottky barrier diodes: Ultra-thin InGaN for high breakdown voltage and low Ron

Elison de Nazareth Matioli, Alessandro Floriduz, Zheng Hao

In this work, we present a concept that leverages the strong piezoelectric polarization field in InGaN, which counteracts the external electric field at reverse bias. We show that despite the smaller InGaN band-gap and lower critical electric field, its st ...

2024

Spin-Reorientation-Driven Linear Magnetoelectric Effect in Topological Antiferromagnet Cu3TeO6

Helmuth Berger

The search for new materials for energy -efficient electronic devices has gained unprecedented importance. Among the various classes of magnetic materials driving this search are antiferromagnets, magnetoelectrics, and systems with topological spin excitat ...

Amer Physical Soc2024

Magneto-Thermoelectric Transport in Graphene Quantum Dot with Strong Correlations

Oleksandr Kriuchkov

Disorder at etched edges of graphene quantum dots (GQD) enables random all-to-all interactions between localized charges in partially filled Landau levels, providing a potential platform to realize the Sachdev-Ye-Kitaev (SYK) model. We use quantum Hall edg ...

2024

Direct observations of X-rays produced by upward positive lightning

Farhad Rachidi-Haeri, Marcos Rubinstein, Antonio Sunjerga, Thomas Chaumont

X-rays have been observed in natural downward cloud-to-ground lightning for over 20 years and in rocket-triggered lightning for slightly less. In both cases, this energetic radiation has been detected during the stepped and dart leader phases of downward n ...

Nature Publishing Group2024

Plasmonic Nanostructures for Photocatalysis: Material, Photonic and Electronic Effects

Fateme Kiani Shahvandi

Plasmonic photochemistry has a large potential to replace energy-intensive chemical processes with low-temperature, low-pressure light-driven chemical reactions. Plasmonic nanostructures have emerged as promising photocatalysts with exceptional and tunable ...

EPFL2024

Exciton migration in two-dimensional materials

Excitons play an essential role in the optical response of two-dimensional materials. These are bound states showing up in the band gaps of many-body systems and are conceived as quasiparticles formed by an electron and a hole. By performing real-time simu ...

Nature Portfolio2024

Charging and Electric Field Effects on Hydrogen Molecules Physisorbed on Graphene

Klaus Kern, Shai Mangel, Alessio Scavuzzo, Tobias Wollandt

Molecular hydrogen adsorbed on graphene was investigated by analyzing rotational excitation spectra obtained with a gate-tunable scanning tunneling microscope (STM). Through the shift of the rotational excitation energy, the tunability of physisorbed H2 on ...

AMER CHEMICAL SOC2023

Topological Effects in Carbon-based Two-dimensional Nanostructures

Yifei Guan

Recent advances on low-dimensional and topological materials has greatly inspired the research in condensed matter physics. This thesis is devoted to the computational and theoretical study of topological effects in two-dimensional materials, especially na ...

EPFL2023

Correlated insulator collapse due to quantum avalanche via in-gap ladder states

Xi Chen, Camille Didier Georges Aron

The significant discrepancy observed between the predicted and experimental switching fields in correlated insulators under a DC electric field far-from-equilibrium necessitates a reevaluation of current microscopic understanding. Here we show that an elec ...

Nature Portfolio2023

Resonant Transducers Consisting of Graphene Ribbons with Attached Proof Masses for NEMS Sensors

Luis Guillermo Villanueva Torrijo, Daniel Moreno Garcia

The unique mechanical and electrical properties of graphene make it an exciting material for nanoelectromechanical systems (NEMS). NEMS resonators with graphene springs facilitate studies of graphene's fundamental material characteristics and thus enable i ...

Amer Chemical Soc2023

Mechanistic study on the evolution of vacancies in graphene by oxidation by scanning tunneling microscopy

Shaoxian Li

Nanostructured graphitic materials, including graphene hosting Å to nanometer-sized pores, have attracted attention for various applications such as separations, sensors, and energy storage. Graphene with Å-scale pores is a promising next-generation materi ...

EPFL2023

Cotton yarns decorated with hydrothermally reduced graphene oxide for flexible supercapacitors

Xing Wang, Dou Du, Lin Li

Cotton fibers, a natural cellulose, have played a critical role in the development of wearable energy storage, owning to their wearability, integrability, eco-benignity, and cost effectiveness. Graphene, a two-dimensional carbon material, possesses excelle ...

Elsevier2023