Affiner les résultats

Thermodynamic Aspects of Homogeneous Nucleation Enhanced by Icosahedral Short Range Order in Liquid Fcc-Type Alloys

Rappaz, Michel ; Kurtuldu, Güven

In: JOM, 2015, vol. 67, no. 8, p. 1812-1820

Ultrafast dynamics of the surface photovoltage in potassium-doped black phosphorus

Kremer, Geoffroy ; Rumo, Maxime ; Yue, Changming ; Pulkkinen, Aki ; Nicholson, Christopher W. ; Jaouen, Thomas ; Von Rohr, Fabian ; Werner, Philipp ; Monney, Claude

In: Physical Review B, 2021, vol. 104, no. 3, p. 035125

Black phosphorus is a quasi-two-dimensional layered semiconductor with a narrow direct band gap of 0.3 eV. A giant surface Stark effect can be produced by the potassium doping of black phosphorus, leading to a semiconductor to semimetal phase transition originating from the creation of a strong surface dipole and associated band bending. By using time- and angle-resolved photoemission ...

Adsorption-induced kondo effect in metal-free phthalocyanine on Ag(111)

Granet, J. ; Sicot, M. ; Gerber, I. C. ; Kremer, Geoffroy ; Pierron, T. ; Kierren, B. ; Moreau, L. ; Fagot-Revurat, Y. ; Lamare, S. ; Chérioux, F. ; Malterre, D.

In: The Journal of Physical Chemistry C, 2020, vol. 124, no. 19, p. 10441–10452

We report on the formation of a two-dimensional supramolecular Kondo lattice made of organic molecules comprising only C, N, and H atoms, namely metal-free phthalocyanines 2HPc (C32H18N8), adsorbed on a Ag(111) surface. Low-temperature scanning tunneling microscopy/spectroscopy (LT-STM/STS), ultraviolet photoemission spectroscopy (UPS), and density functional theory (DFT) are used to...

Role of a higher-dimensional interaction in stabilizing charge density waves in quasi-one-dimensional ${\mathrm{NbSe}}_{3}$ revealed by angle-resolved photoemission spectroscopy

Nicholson, Christopher W. ; Schwier, Eike Fabian ; Shimada, K. ; Berger, Helmuth ; Hoesch, M. ; Berthod, C. ; Monney, Claude

In: Physical Review B, 2020, vol. 101, no. 4, p. 045412

We revisit charge density wave (CDW) behavior in the archetypal quasi-one- dimensional (quasi-1D) material NbSe3 by high-resolution angle-resolved photoemission spectroscopy measurements utilizing a microfocused laser with a photon energy of 6.3 eV. We present a detailed view of the electronic structure of this complex multiband system and unambiguously resolve CDW gaps at the Fermi level ...

Phase separation in the vicinity of Fermi surface hot spots

Jaouen, Thomas ; Hildebrand, Baptiste ; Mottas, Marie-Laure ; Giovannantonio, M. Di ; Ruffieux, Pascal ; Rumo, Maxime ; Nicholson, Christopher W. ; Razzoli, E. ; Barreteau, C. ; Ubaldini, A. ; Giannini, E. ; Vanini, Fabiano ; Beck, Hans ; Monney, Claude ; Aebi, Philipp

In: Physical Review B, 2019, vol. 100, no. 7, p. 075152

Spatially inhomogeneous electronic states are expected to be key ingredients for the emergence of superconducting phases in quantum materials hosting charge-density waves (CDWs). Prototypical materials are transitionmetal dichalcogenides (TMDCs) and among them, 1T-TiSe2 exhibiting intertwined CDW and superconducting states under Cu intercalation, pressure, or electrical gating. Although it...

Phase transformation of superparamagnetic iron oxide nanoparticles via thermal annealing: implications for hyperthermia applications

Crippa, Federica ; Rodriguez-Lorenzo, Laura ; Hua, Xiao ; Goris, Bart ; Bals, Sara ; Garitaonandia, José S. ; Balog, Sandor ; Burnand, David ; Hirt, Ann M. ; Haeni, Laetitia ; Lattuada, Marco ; Rothen-Rutishauser, Barbara ; Petri-Fink, Alke

In: ACS Applied Nano Materials, 2019, vol. 2, no. 7, p. 4462–4470

Magnetic hyperthermia has the potential to play an important role in cancer therapy and its efficacy relies on the nanomaterials selected. Superparamagnetic iron oxide nanoparticles (SPIONs) are excellent candidates due to the ability of producing enough heat to kill tumor cells by thermal ablation. However, their heating properties depend strongly on crystalline structure and size, which may...

Excited-state band mapping and momentum-resolved ultrafast population dynamics in In/Si(111) nanowires investigated with XUV-based time- and angle-resolved photoemission spectroscopy

Nicholson, Christopher W. ; Puppin, M. ; Lücke, A. ; Gerstmann, U. ; Krenz, M. ; Schmidt, W. G. ; Rettig, L. ; Ernstorfer, R. ; Wolf, M.

In: Physical Review B, 2019, vol. 99, no. 15, p. 155107

We investigate the excited state electronic structure of the model phase transition system In/Si(111) using femtosecond time- and angle-resolved photoemission spectroscopy (trARPES). An extreme ultraviolet 500 kHz laser source at 21.7 eV is utilized both to map the energy of excited states above the Fermi level and follow the momentum-resolved population dynamics on a femtosecond timescale....

Time- and angle-resolved photoemission spectroscopy of solids in the extreme ultraviolet at 500 kHz repetition rate

Puppin, M. ; Deng, Y. ; Nicholson, Christopher W. ; Feldl, J. ; Schröter, N. B. M. ; Vita, H. ; Kirchmann, P. S. ; Monney, Claude ; Rettig, L. ; Wolf, M. ; Ernstorfer, R.

In: Review of Scientific Instruments, 2019, vol. 90, no. 2, p. 023104

Time- and angle-resolved photoemission spectroscopy (trARPES) employing a 500 kHz extreme-ultraviolet light source operating at 21.7 eV probe photon energy is reported. Based on a high-power ytterbium laser, optical parametric chirped pulse amplification, and ultraviolet-driven high-harmonic generation, the light source produces an isolated high-harmonic with 110 meV bandwidth and a flux of...

Non-uniform doping across the Fermi surface of NbS2 intercalates

Battaglia, C. ; Cercellier, H. ; Despont, L. ; Monney, C. ; Prester, M. ; Berger, H. ; Forró, L. ; Garnier, M. G. ; Aebi, P.

In: The European Physical Journal B, 2007, vol. 57, no. 4, p. 385-390

Transformation properties and microstructure of sputter-deposited Ni-Ti shape memory alloy thin films

Lehnert, T. ; Crevoiserat, S. ; Gotthardt, R.

In: Journal of Materials Science, 2002, vol. 37, no. 8, p. 1523-1533