Publications related to Na2V3O7: An unusual low-dimensional quantum magnet

Field-controlled multicritical behavior and emergent universality in fully frustrated quantum magnets

Phase transitions in condensed matter are a source of exotic emergent properties. We study the fully frustrated bilayer Heisenberg antiferromagnet to demonstrate that an applied magnetic field creates a previously unknown emergent criticality. The quantum ...

Nature Portfolio2024

Molecular intercalation in the van der Waals antiferromagnets FePS3 and NiPS3

Bruce Normand, Xiaoyu Xu, Sheng Xu, Ying Chen, Zeyu Wang, Shuo Li, Weiqiang Yu

We have performed electrochemical treatment of the van der Waals antiferromagnetic materials FePS3 and NiPS3 with the ionic liquid EMIM-BF4, achieving significant molecular intercalation. Mass analysis of the intercalated compounds, EMIMx-FePS3 and EMIMx-N ...

Amer Physical Soc2024

Symmetry-Induced Singlet-Triplet Inversions in Non-Alternant Hydrocarbons

Anne-Clémence Corminboeuf, Jacob Terence Blaskovits, Marc Hamilton Folkmann Garner

Molecules with inversion of the singlet and triplet excited-state energies are highly promising for the development of organic light-emitting diodes (OLEDs). To date, azaphenalenes are the only class of molecules where these inversions have been identified ...

Wiley-VCH Verlag GmbH2023

Experimental study of stability, quench propagation and detection methods on 15 kA sub-scale HTS fusion conductors in SULTAN

Pierluigi Bruzzone, Kamil Sedlák, Nikolay Bykovskiy, Ortensia Dicuonzo

High-temperature superconductors (HTSs) enable exclusive operating conditions for fusion magnets, boosting their performance up to 20 T generated magnetic fields in the temperature range from 4 K to 20 K. One of the main technological issues of HTS conduct ...

2023

Scaling Description of Dynamical Heterogeneity and Avalanches of Relaxation in Glass-Forming Liquids

Ali Tahaei, Matthieu Wyart

We provide a theoretical description of dynamical heterogeneities in glass-forming liquids, based on the premise that relaxation occurs via local rearrangements coupled by elasticity. In our framework, the growth of the dynamical correlation length e and o ...

American Physical Society2023

Single molecule fluorescence and phosphorescence studies using a scanning tunneling microscope

Abhishek Grewal

This thesis investigates novel single-molecule luminescence phenomena at their inherent, sub-molecular length scale. The microscopic understanding of luminescence processes will be crucial for the continued improvement of organic optoelectronic and semicon ...

EPFL2022

Photochemical oxidation of phenols and anilines mediated by phenoxyl radicals in aqueous solution

Silvio Canonica, Urs von Gunten, Stephanie Christa Remke

Reactive intermediates formed upon irradiation of chromophoric dissolved organic matter (CDOM) contribute to the degradation of various organic contaminants in surface waters. Besides well-studied "short-lived" photo oxidants, such as triplet state CDOM (3 ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Canted antiferromagnetic phases in the candidate layered Weyl material EuMnSb2

Xiaoqiang Wang, Xiao Wang

EuMnSb2 is a candidate topological material which can be tuned towards a Weyl semimetal, but there are differing reports for its antiferromagnetic (AFM) phases. The coupling of bands dominated by pure Sb layers hosting topological fermions to Mn and Eu mag ...

AMER PHYSICAL SOC2022

Possibility to detect the bound state of the Heisenberg ferromagnetic chain at intermediate temperature

Frédéric Mila, Mithilesh Nayak

Motivated by the lack of direct evidence with inelastic neutron scattering of the well documented bound state of Heisenberg ferromagnets, we use the time-dependent thermal density matrix renormalization group algorithm to study the temperature dependence o ...

2022

VO2:Ge based thermochromic solar absorber coatings

Josef Andreas Schuler, Anna Krammer

Flat plate solar collectors face the problem of overheating and the ensuing high thermal stresses and general collector damage lead to high maintenance costs. To address this challenge, absorber coatings with a passive optical switch at critically high ope ...

ELSEVIER2022

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

Classical Spin Liquid or Extended Critical Range in h-YMnO3?

Sofie Janas, Jakob Lass

Neutron spectroscopy on the classical triangular-lattice frustrated antiferromagnet h-YMnO3 reveals diffuse, gapless magnetic excitations present both far below and above the ordering temperature. The correlation length of the excitations increases as the ...

AMER PHYSICAL SOC2021

How free exciton-exciton annihilation lets bound exciton emission dominate the photoluminescence of 2D-perovskites under high-fluence pulsed excitation at cryogenic temperatures

Michael Graetzel, Jovana Milic, Yang Li, Algirdas Ducinskas

Photoluminescence (PL) spectra of atomically thin 2D lead iodide perovskite films are shown to depend on excited-state density, especially at cryogenic temperatures. At high excited-state densities and low temperatures, free exciton (FE) emission is so sup ...

AMER INST PHYSICS2021

Dynamical properties of a driven dissipative dimerized S=1/2 chain

Bruce Normand

We consider the dynamical properties of a gapped quantum spin system coupled to the electric field of a laser, which drives the resonant excitation of specific phonon modes that modulate the magnetic interactions. We deduce the quantum master equations gov ...

2021

Strong temperature-dependent thermoelectric power of IrMn(3)thin films of different thicknesses

Jean-Philippe Ansermet, Haiming Yu, Junfeng Hu, Mukund Krishna Kothari

IrMn(3)thin films were experimentally characterized by thermoelectric power and resistivity as a function of temperature and sample thickness. The Seebeck coefficient shows strong temperature dependence and the value increases with temperature up to 350 K. ...

IOP PUBLISHING LTD2021

Transport signatures of temperature-induced chemical potential shift and Lifshitz transition in layered type-II Weyl semimetal TaIrTe4

Oleg Yazyev, Quansheng Wu, Meng Yang

Temperature-induced Lifshitz transitions have been identified in several materials. Their chemical potential shows a substantial shift with changing temperature. The common feature of these materials is the coexistence of electron and hole pockets in the v ...

IOP PUBLISHING LTD2021

Scanning SQUID microscopy in a cryogen-free dilution refrigerator

Philip Johannes Walter Moll, Maja Deborah Bachmann

We report a scanning superconducting quantum interference device (SQUID) microscope in a cryogen-free dilution refrigerator with a base temperature at the sample stage of at least 30 mK. The microscope is rigidly mounted to the mixing chamber plate to opti ...

2021

Molecular Origin of the Asymmetric Photoluminescence Spectra of CsPbBr3 at Low Temperature

Michael Graetzel, Ursula Röthlisberger, Gwénolé Jean Jacopin, Mohammad Ibrahim Dar, Ariadni Boziki

CsPbBr3 has received wide attention due to its superior emission yield and better thermal stability compared to other organic-inorganic lead halide perovskites. In this study, through an interplay of theory and experiments, we investigate the molecular ori ...

2021

Gas-puff induced cold pulse propagation in ADITYA-U tokamak

Abhijit Sen, Harshita Raj, Ankit Kumar, Rohit Kumar

Short bursts (similar to 1 ms) of gas, injecting similar to 10(17)-10(18) molecules of hydrogen and/or deuterium, lead to the observation of cold pulse propagation phenomenon in hydrogen plasmas of the ADITYA-U tokamak. After every injection, a sharp incre ...

IOP Publishing Ltd2021

Phototransformation of Organic Contaminants in Aquatic Systems: Characterization of Long-Lived Photooxidants Derived from Dissolved Organic Matter

Stephanie Christa Remke

The increasing interest in the fate of organic contaminants in the aquatic environment requires the elucidation of relevant abiotic transformation processes. These processes often involve the ubiquitous dissolved organic matter (DOM), a complex mixture of ...

EPFL2021