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Magnetic systems with competing interactions often adopt exotic ground states, which can be relevant to study new physics in quantum matter [1]. A recurrent ingredient to stabilize such phases is frustration, such as in pyrochlore oxides where rare-earth magnetic moments decorate a lattice of corner-sharing tetrahedra. An unusual spin liquid appears for example in the pyrochlore Ho2Ti2O7, which features a classical ‘spin ice’ short-range correlated state [2,3]. A local constraint – the 2-in-2-out ‘ice rule’ acting on each tetrahedron – leads to a manifold of degenerate ground states in which the spin correlations give rise to emergent magnetostatics [4]. Spin flips violating the ice rule generate magnetic monopole excitations [5], a mobile magnetic charge regarded as a quasiparticle carrying half of the dipole moment. A quantum analogue of the spin ice state is predicted to be a special type of quantum spin liquid formed through the coherent superposition of spin ice configurations [6,7]. Remarkably, the low-energy physics of this quantum spin ice state is predicted to be a lattice analogue of quantum electrodynamics. We review recent results on tracking the experimental signatures of quantum mechanical ground states in rare-earth pyrochlores such as Pr2Hf2O7 [8-9] and Ce2Sn2O7 [10-11].
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11. Sibille, R. et al. Nature Physics 16, 546-552 (2020).
| 2020 - present | Senior scientist Laboratory for Neutron Scattering and Imaging, PSI |
| 2016-2020 | Tenure-track scientist Laboratory for Neutron Scattering and Imaging, PSI |
| 2012-2016 | Postdoctoral researcher Laboratory for Scientific Developments and Novel Materials, PSI |
| 2009-2012 | PhD studies (Dr. chemistry) and teaching Institute Jean Lamour and Université de Lorraine |
| 2007-2009 | Master in Matter Sciences ('Molecules, Materials and Surfaces) and research internship, Université Paris Diderot and ITODYS laboratory |
| 2004-2007 | BSc in Matter Sciences ('Chemistry and Physical Chemistry'), Nancy Université |