Jean-Philippe Ansermet

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Magnons can transfer information in metals and insulators without Joule heating, and therefore are promising for low-power computation. The on-chip magnonics however suffers from high losses due to limited magnon decay length. In metallic thin films, it is ...

Topological quantum materials have stimulated growing attention because they reveal novel aspects of condensed matter physics and point to new opportunities in materials science, in particular for thermoelectrics. Here, we experimentally study thermoelectr ...

Since their discovery in 1927, the Heisenberg Inequalities have become an icon of quantum mechanics. Often inappropriately referred to as the Uncertainty Principle, these inequalities relating the standard deviations of the position and momentum observables to Planck's constant are one of the cornerstones of the quantum formalism even if the physical interpretation of quantum mechanics remains still open to controversy nowadays. The Heisenberg Inequalities governing translational motion are well understood.

Long needle-shaped single crystals of Zn1-xCoxO were grown at low temperatures using a molten salt solvent technique, up to x=0.10. The conduction process at low temperatures is determined to be Mott variable range hopping. Both pristine and cobalt-doped c ...

We present a detailed discussion of the evolution of a statistical ensemble of quantum mechanical systems coupled weakly to a bath. The Hilbert space of the full system is given by the tensor product between the Hilbert spaces associated with the bath and the bathed system. The statistical states of the ensemble are described in terms of density matrices. Supposing the bath to be held at some - not necessarily thermal - statistical equilibrium and tracing over the bath degrees of freedom, we obtain reduced

We report on the effect of a low amplitude microwave current on the switching field of magnetic layers in a 40 nm diameter pseudo-spin valve grown by template synthesis. We show a frequency dependence at room temperature reflecting the dynamic behavior of ...

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 ...

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 ...

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. ...

Low-cost spintronic devices functioning in zero applied magnetic field are required for bringing the idea of spin-based electronics into the real-world industrial applications. Here we present first microwave measurements performed on nanomagnet devices fa ...

Transport measurements are carried out in which temperature oscillation is applied to magnetic nanostructures. Using spin valves, this measurement reveals aspects of the spin transport in non-collinear configurations. In one implementation, an AC voltage i ...

The existence of a heat-driven spin torque is demonstrated using Co/Cu/Co spin valves embedded in metallic nanowires. Heat currents flowing in one direction or its opposite were obtained by heating optically one end or the other of the nanowires. The spin ...

We present magnetization and Se-77 Nuclear Magnetic Resonance (NMR) measurements in single crystals of the magnetoelectric compound Cu2OSeO3. The temperature and field dependence of the magnetization suggest a ferrimagnetic ordering at T-c similar or equal to 60 K in a 3up-1down configuration. The easy axis of the magnetization is along the [100] crystallographic direction. The Se-77 NMR line shape data collected at 14.09 T are consistent with the symmetries imposed by the cubic P2(1)3 space group in the te

Hyperpolarized nuclear spins are observed in optically pumped iron-doped InP from 70 K to 140 K. P-31 NMR was carried out at 9.28 T (159.8 MHz) during optical excitation with circularly polarized light, using a laser diode (lambda-830 nm) as a source. The ...

Spin-dependent transport properties of nanowires containing individual Co/Cu/Co pseudo-spin valves were investigated by monitoring an AC voltage induced by a temperature oscillation under a continuous DC current. We observed sharp peaks in the field-depend ...

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 ...

The mixed effects of heat and charge transports have been studied at room temperature for NiCu and CoCu multilayers with currents perpendicular to the interfaces as well as Ni and Co homogeneous nanowires. In order to carry out this analysis, magnetothermo ...

By means of a diffusive description of spin-dependent thermal and electrical transport using Pauli-spin matrices, we analyze the spin-dependent transport mechanisms that determine the voltage response of a metallic spin valve to an ac temperature oscillati ...

The thermodynamics of irreversible processes in continuous media predicts the existence of a magnetic Nernst effect that results from a magnetic analog to the Seebeck effect in a ferromagnet and magnetophoresis occurring in a paramagnetic electrode in cont ...

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 ...

Jean-Philippe Ansermet

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Long decay length of magnon-polarons in BiFeO3/La0.67Sr0.33MnO3 heterostructures

Large magnetothermopower and anomalous Nernst effect in HfTe5

Rotational Heisenberg Inequalities

Low-temperature hopping and absence of spin-dependent transport in single crystals of cobalt-doped ZnO

Dissipative evolution of quantum statistical ensembles and nonlinear response to a time-periodic perturbation

Switching field modulation of a nanomagnet by resonant microwave spin torque

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

Spin Evolution in the Born-Oppenheimer Approximation

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

Template Nanowires for Spintronics Applications: Nanomagnet Microwave Resonators Functioning in Zero Applied Magnetic Field

Heat and spin transport in magnetic nanowires

Linear response to a heat-driven spin torque

Magnetic properties of the magnetoelectric compound Cu2OSeO3: Magnetization and Se-77 NMR study

Nuclear polarization by optical pumping in InP:Fe above liquid nitrogen temperature

Temperature derivative of the resistance of spin valves

Cavity-Mediated Coupling of Terahertz Antiferromagnetic Resonators

Thermoelectrical study of ferromagnetic nanowire structures

Second-harmonic response and temperature differential resistivity of noncollinear spin valves

Magnetic Nernst effect

Magic-angle magnonic nanocavity in a magnetic moiré superlattice