Exotic Correlated Quantum States
In a nutshell, I am interested in what happens when electrons are not happy to live together in a crystal.
Somewhat less colloquially, magnetic materials are made of atoms (or more precisely ions) carrying a magnetic spin. Our problem at hand is that in some of these materials, all interactions between the spins cannot always be satisfied at the same time. This leads to what is called magnetic frustration and hinders, sometimes even prevents, the system to order on long length scales. In our everyday life, it would be the same as a cup of water that would never freeze, even in the middle of Antarctica !
For scientists, frustration has opened a window to explore some of the hidden properties of matter at very low temperature, which is where quantum mechanics rules. I spend most of my time looking through this window, trying to make sense of what I see.
The absence of order often leads to persistent fluctuations, paradoxically coupled to strong correlations between spins and quantum entanglement. In this field, I am especially interested in emergent phenomena, spin liquids, topological phases … and more generally to the connections between Condensed Matter and Statistical Physics, such as in loop models.
since 2017: CNRS researcher at the LOMA, University of Bordeaux, France
2013 – 2016: Group leader at the Okinawa Institute of Science & Techonology (OIST), Japan
2012 – 2012: Postdoc at OIST, Okinawa, Japan
2009 – 2011: Postdoc at the Max Planck Institute (PkS), Dresden, Germany
2006 – 2009: Ph.D student and teaching assistant at the ENS Lyon, France
2002 – 2006: Normalien of the ENS Lyon, France (Master and last year of License)
2015 ENS Lyon, France (1 month, guest professor)
2012 Oxford University, UK (8 months)
2010 Waterloo University, Canada (1 month)
2009 Waterloo University, Canada (1 month)
2007 Oxford University, UK (4 months)
2006 Campinas University, Brazil (1 month)
2006 Pierre & Marie Curie University, Paris, France (4 months, intern)
2004 Campinas University, Brazil (3 months, intern)
Karim Essafi, Owen Benton, L.D.C. Jaubert
Generic nearest-neighbour kagome model: XYZ & Dzyaloshinskii-Moriya, and comparison to pyrochlore
M. Taillefumier, O. Benton, H. Yan, L.D.C. Jaubert, N. Shannon
Frustrating quantum spin ice: a tale of three spin liquids, and hidden order
24. Journal of Physics: Condensed Matter 29, 315802 (2017) [arXiv]
K. Essafi, L.D.C. Jaubert & M. Udagawa
Flat bands and Dirac cones in breathing lattices
23. Physical Review Letters 118, 207206 (2017) [arXiv]
L.D.C. Jaubert , T. Lin, T.S. Opel, P.C.W. Holdsworth & M.J.P. Gingras
Spin Ice Thin Film: Surface Ordering, Emergent Square Ice and Strain Effects
22. Physical Review B 95, 094422 (2017) [arXiv]
H. Yan , O. Benton, L.D.C. Jaubert & N. Shannon
Theory of multiple-phase competition in pyrochlore magnets with anisotropic exchange, with application to Yb2Ti2O7, Er2Ti2O7 and Er2Sn2O7
16. Physical Review Letters 115, 267208 (2015) [arXiv]
L.D.C. Jaubert, O. Benton, J.G. Rau, J. Oitmaa, R.R.P. Singh, N. Shannon & M.J.P. Gingras
Are mulitphase competition & order-by-disorder the keys to understanding Yb2Ti2O7 ?
15. Spin 5, 1540005 (2015) [arXiv]
Monopole holes in a Partially Ordered Spin Liquid
# invited paper for the special issue on “Quantum Spin Ice and Liquid in Geometrically Frustrated Magnets”
12. Journal of Physics: Condensed Matter 25, 386002 (2013) [arXiv]
L. Bovo, L.D.C. Jaubert, P.C.W. Holdsworth & S.T. Bramwell
Crystal Shape-Dependent Magnetic Susceptibility and Curie Law Crossover in the Spin Ices Dy2Ti2O7 and Ho2Ti2O7
11. Physical Review X 3, 011014 (2013) [arXiv]
L.D.C. Jaubert, M.J. Harris, T. Fennell, R.G. Melko, S.T. Bramwell & P.C.W. Holdsworth
Topological Sector Fluctuations and Curie Law Crossover in Spin Ice
8. Journal of Physics: Condensed Matter 23, 164222 (2011) [arXiv]
L.D.C. Jaubert & P.C.W. Holdsworth
Magnetic Monopole Dynamics in Spin Ice
6. Nature Physics 5, 258-261 (2009) [arXiv]
L.D.C. Jaubert & P.C.W. Holdsworth
Signature of magnetic monopole and Dirac string dynamics in spin ice
# selected as one of the 12 featured articles for the 10-year anniversary of Nature Physics in 2015
5. Journal of Physics: Conference Series 145, 012024 (2009) [arXiv]
L.D.C. Jaubert, J.T. Chalker, P.C.W. Holdsworth & R. Moessner
A three dimensional Kasteleyn transition in spin ice
Ecole Normale Supérieure de Lyon (Sept. 2006 – Sept. 2009)
Topological Constraints and Defects in Spin Ice
Karim Essafi (a.k.a. Obiwan) – Postdoc
I completed my PhD with Dominique Mouhanna at the University Pierre and Marie Curie in 2012. In November 2013, I joined the TQM Unit at OIST. I am interested in phase transitions and critical phenomena. During my PhD, I specialised in the study of critical phenomena using the nonperturbative renormalisation group (NPRG). Outside of work, I enjoy playing and watching football, diving and surfing.
Rico Pohle – Ph.D student, co-supervised with Nic Shannon
I received my diploma in experimental physics from the Dresden University of Technology (Germany) in 2012. During my diploma I studied surface properties of
the unconventional pnictide superconductor LiFeAs with an Scanning Tunneling Microscope. After joining the PhD program of the Okinawa Institute of Science and Technology Graduate University (OIST) as one of its first students, I switched to theoretical physics and try to enlarge my understanding of thermodynamical and dynamical properties in spin liquids. Next to my studies I am very interested in martial arts, dancing and the exploration of the culture, history and spirit of the islands of Okinawa and Japan.
Interns (~3 months)
2016 – Victor Drouin-Touchette (B.Sc, University of Montreal, Canada, co-supervision with Karim Essafi)
=> Graduate school at Rutgers, USA.
2015 – Maxime Garnier (Master 1, ENS Cachan, France) => Master 2 at ENS Ulm, Paris.
2013 – Valentin Raban (Master 1, ENS Lyon, France) => Ph.D with Peter Holdsworth at ENS Lyon.
2012 – Han Yan (Part III, Cambridge, UK, co-supervision with Nic Shannon)
=> long-term collaborator & Ph.D with Prof. Sugawara in string theory at OIST.
OIST Graduate school students (4 months)
2014 – Christina Lee (B.Sc Physics, Caltech, USA) => Ph.D with Nic Shannon at OIST.
2013 – Tosif Ahamed (Master Cognitive Science, Edinburgh, Scotland)
=> Ph.D at the interface between neuroscience (Prof. Maruyama) and biophysics (Prof. Stevens) at OIST.
2012 – Rico Pohle (Master Physics, Dresden) => Ph.D with Nic Shannon and me at OIST (see above).
2015 – 2016: OIST, Japan | Master course in « Advanced Statistical Mechanics » (20 hours)
2012 – 2014: OIST, Japan | Master course in « Advanced Statistical Mechanics » (30 hours / year)
2006 – 2009: Ecole Normale Superieure of Lyon, France (64 hours / year)
• Lab works (Master): electronic, thermodynamic, electromagnetism…
• Quantum Mechanics tutorials (B.Sc)
2005: Master in Education: “Agrégation de Sciences Physiques”
National competitive exam, to teach at B.Sc and Highschool level
2000 – 2004: Highschool tutor
You can find here a few articles written by science journalists about the research we have done over the years.
2016 “Spin Liquid on a peak” by Greta Keenan (OIST, Japan)
2016 “The Quest for Spin Liquids” by Rebecca Hofland (OIST, Japan)
2015 “Magnetic Monopoles: Crystal Clear” by Letizia Diamante (OIST, Japan)
2010 “Premiers monopôles magnétiques” by Franck Daninos (La Recherche, France), in french
2009 “Hunting the mysterious monopole” by Eugenie Reich (New Scientist, UK)
2009 “Trolling for poles” (Nature Research Highlights, UK)
Laboratoire Ondes et Matière d’Aquitaine (LOMA)
351 cours de la libération
33405 Talence Cedex
Phone : + 33 (0)5 40 00 3732