Publications by Jean-Philippe Ansermet

Coherent magnon transport in a van der Waals antiferromagnet

Recently developed van der Waals magnets offer a promising platform for advancing spintronics. The weak interlayer antiferromagnetic exchange coupling in van der Waals antiferromagnets allows for unique spin dynamics and control over magnons. In this study ...

AIP Publishing2025

Long-range propagation of magnon polaritons in a canted antiferromagnet

Jean-Philippe Ansermet

American Physical Society (APS)2025

Deterministic switching of antiferromagnetic spin textures by nonlinear magnons

Jean-Philippe Ansermet, Dirk Grundler, Mohammad Hamdi, Mingran Xu

Antiferromagnetic spin textures, compared to their ferromagnetic counterparts, innately possess high stability with respect to external disturbance and high-frequency dynamics compatible with ultrafast information processing. However, deterministic creatio ...

DIN Media GmbH2025

Coupling between electrons’ spin and proton transfer in chiral biological crystals

Jean-Philippe Ansermet

Proton transport plays a fundamental role in many biological and chemical systems. In life, proton transport is crucial for biochemical and physiological functions. It is usually accepted that the main mechanism of proton transfer is a result of hopping be ...

Proceedings of the National Academy of Sciences2025

Control of spin currents by magnon interference in a canted antiferromagnet

Jean-Philippe Ansermet, Peng Chen, Dirk Grundler, Keita Yamamoto, Junfeng Hu

Controlling the spin current lies at the heart of spintronics and its applications. In ferromagnets, the sign of spin currents is fixed once the current direction is determined. However, spin currents in antiferromagnets can possess opposite polarizations, ...

Springer Science and Business Media LLC2025

Observation of Coherent Gapless Magnons in an Antiferromagnet

Jean-Philippe Ansermet

Antiferromagnetic magnons possess high speed and are immune to external disturbance, making them promising for future magnonic circuits. In this Letter, we report the observation of gapless magnons in an easy-axis antiferromagnet alpha-Fe2O3 at low tempera ...

AMER PHYSICAL SOC2025

Magnon gap excitations in van der Waals antiferromagnet MnPSe3

Jean-Philippe Ansermet

Magneto-spectroscopy methods have been employed to study the zero-wavevector magnon excitations in MnPSe3. Experiments carried out as a function of temperature and the applied magnetic field show that two low-energy magnon branches of MnPSe3 in its antifer ...

Nature Research2024

Enhancement of electrocatalysis through magnetic field effects on mass transport

Jean-Philippe Ansermet, Magalí Alejandra Lingenfelder, Yunchang Liang

Magnetic field effects on electrocatalysis have recently gained attention due to the substantial enhancement of the oxygen evolution reaction (OER) on ferromagnetic catalysts. When detecting an enhanced catalytic activity, the effect of magnetic fields on ...

Nature Portfolio2024

Broad-wave-vector spin pumping of flat-band magnons

Jean-Philippe Ansermet

We report the experimental observation of large spin -pumping signals in the YIG/Pt system driven by broad -wave -vector spin -wave spin current. 280-nm-wide microwave inductive antennas offer broad -wavevector excitation, which, in combination with the qu ...

American Physical Society (APS)2024

Long-distance coherent propagation of magnon polarons in a ferroelectric-ferromagnetic heterostructure

Jean-Philippe Ansermet, Haiming Yu, Peng Chen, Song Liu, Jilei Chen, Jianyu Zhang, Jinlong Wang, Yao Zhang

We experimentally demonstrate the coherent propagation of magnon polarons, the hybridized excitations formed by the coupling of spin waves and Rayleigh/Love surface acoustic waves, in a heterostructure consisting of ferroelectric BaTiO3 and ferromagnetic L ...

Amer Physical Soc2023

Cavity-Mediated Coupling of Terahertz Antiferromagnetic Resonators

Jean-Philippe Ansermet, Marcin Bialek

Coupling of space-separated resonators is interesting for quantum and communication technologies. In this work, we show that antiferromagnetic resonance in separated parallel-plane slabs of hematite (alpha-Fe2O3) couple cooperatively to terahertz electroma ...

American Physical Society (APS)2023

Hybridized Propagation of Spin Waves and Surface Acoustic Waves in a Multiferroic-Ferromagnetic Heterostructure

Jean-Philippe Ansermet

Coherent coupling in magnon-based hybrid systems has many potential applications in quantum information processing. Magnons can propagate in magnetically ordered materials without any motion of electrons, offering a unique method to build low-power-consump ...

American Physical Society (APS)2023

Optically Enhanced Solid-State H-1 NMR Spectroscopy

Jean-Philippe Ansermet, Jonas Milani, Dominik Józef Kubicki, David Lyndon Emsley, Aaron James Rossini, Claudia Esther Avalos, Gabriele Stevanato, Aditya Mishra, Michael Allan Hope, Federico De Biasi, Moreno Lelli, Saumya Badoni

Low sensitivity is the primary limitation to extendingnuclearmagnetic resonance (NMR) techniques to more advanced chemical andstructural studies. Photochemically induced dynamic nuclear polarization(photo-CIDNP) is an NMR hyperpolarization technique where ...

AMER CHEMICAL SOC2023

Long-Distance Coherent Propagation of High-Velocity Antiferromagnetic Spin Waves

Jean-Philippe Ansermet, Haiming Yu, Song Liu, Jilei Chen, Cheng Song, Rundong Yuan, Yao Zhang

We report on coherent propagation of antiferromagnetic (AFM) spin waves over a long distance (similar to 10 mu m) at room temperature in a canted AFM alpha-Fe2O3 owing to the Dzyaloshinskii-Moriya interaction (DMI). Unprecedented high group velocities (up ...

AMER PHYSICAL SOC2023

Reconfigurable nonreciprocal excitation of propagating exchange spin waves in perpendicularly magnetized yttrium iron garnet thin films

Jean-Philippe Ansermet, Haiming Yu, Peng Chen, Jilei Chen, Jinlong Wang, Tao Liu, Rundong Yuan, Yu Zhang

We report the nonreciprocal excitation of propagating forward volume exchange spin waves in yttrium iron garnet (YIG) thin film with perpendicular anisotropy by bringing the in-plane magnetization of Co20Fe60B20 (CoFeB) nanowires to resonance. All-electric ...

Amer Physical Soc2023

Nonlocal Detection of Interlayer Three-Magnon Coupling

Jean-Philippe Ansermet, Haiming Yu, Song Liu, Jilei Chen, Yu Zhang

A leading nonlinear effect in magnonics is the interaction that splits a high-frequency magnon into two low-frequency magnons with conserved linear momentum. Here, we report experimental observation of nonlocal three-magnon scattering between spatially sep ...

AMER PHYSICAL SOC2023

Dnp biosensor

Jean-Philippe Ansermet, Jonas Milani, Felipe Andres Saenz Padilla, Mika Antero Tamski

Method for detecting a change in molecular tumbling of an electron-spin labelled system (1) in solution. Nuclear spins of the entire solution are measured in solution using Overhauser dynamic nuclear polarization in a first reference measurement, and then ...

2022

Hyperactivity of the default mode network in schizophrenia and free energy: A dialogue between Freudian theory of psychosis and neuroscience

Jean-Philippe Ansermet, Pierre Magistretti

The economic conceptualization of Freudian metapsychology, based on an energetics model of the psyche's workings, offers remarkable commonalities with some recent discoveries in neuroscience, notably in the field of neuroenergetics. The pattern of cerebral ...

FRONTIERS MEDIA SA2022

Spin Evolution in the Born-Oppenheimer Approximation

Jean-Philippe Ansermet, Klaus Maschke, François Reuse

The first part of this article attempts to highlight in chronological order some prominent papers that have direct connexion with the Born-Oppenheimer approximation. This timeline successively points to the role of level crossing, the notions of gauge fiel ...

WILEY-V C H VERLAG GMBH2022

Magic-angle magnonic nanocavity in a magnetic moiré superlattice

Jean-Philippe Ansermet, Haiming Yu, Song Liu, Jilei Chen, Jianyu Zhang, Wenhao Jiang, Yao Zhang

Moiré superlattices have recently been extensively studied in both electronic and photonic systems, e.g., magic-angle bilayer graphene showing superconductivity and twisted bilayer photonic crystals leading to magic-angle lasers. However, the moiré physics ...

AMER PHYSICAL SOC2022