Corentin Morice



E-mail: corentin.morice@uva.nl      

I am a postdoctoral researcher working with Jasper van Wezel in the University of Amsterdam. Previously, I was working with Prof. Dr. Arno P. Kampf and Prof. Dr. Thilo Kopp at the University of Augsburg, and Dr. Catherine Pépin at the Institut de Physique Théorique, CEA, Université Paris-Saclay. My PhD was supervised by Prof. Siddharth S. Saxena (Quantum Matter Group) and Prof. Emilio Artacho (Theory of Condensed Matter Group) and funded by the EPSRC and Corpus Christi College at the Cavendish Laboratory, University of Cambridge.

Below is a description of my current and past research interests:

Finite-size topological insulators

I am currently investigating the influence of finite thickness on properties of topological insulators.

We studied this using a minimal model for topological insulators in a slab geometry. One parameter of our model, namely the Dirac velocity perpendicular to the slab, distinguishes between two qualitatively distinct situations: when it is zero, we find that the topological invariants of the 3D system can be entirely deduced from properties of the slab. However when it is not zero, a new phase arises, with surface states but without band inversion. We also investigated this model for large dispersions perpendicularly to the slab and unveiled a regime where the slab displays non-trivial topological invariants but nonetheless extrapolates towards a trivial 3D state.

Publication

C. Morice, T. Kopp, A. P. Kampf
Non-unique connection between bulk topological invariants and surface physics
Phys. Rev. B 100, 235427 (2019)

Quantum bicriticality

At very low temperature, novel quantum effects arise and display mesmerising physics. In particular, close to quantum phase transitions, quantum fluctuations modify properties even at high temperature. The proximity to two quantum phase transitions instead of one could therefore lead to very interesting phenomena. I studied systems where two order parameters are coupled, close to both their quantum phase transitions.

We found that, if the coupling between order parameters is biquadratic, the susceptibilities of both order parameter fields have the same critical exponent over a wide temperature range, even if the exponents of the non-coupled order parameters are different. This finding strongly challenges the conventional characterization of a quantum phase transition in terms of asymptotic exponents.

Quantum bicriticality


Publication

C. Morice, P. Chandra, S. E. Rowley, G. Lonzarich and S. S. Saxena
Hidden fluctuations close to a quantum bicritical point
Phys. Rev. B 96, 245104 (2017)

SU(2) theory of cuprate superconductors

Cuprates have attracted great attention since they were shown to display superconductivity at a remarkably high temperature, above 150 K in some cases. However the process causing this phenomenon is not properly understood yet.

A theory based on an SU(2) order parameter for the pseudogap has been able to explain a series of features of the phase diagram of these materials. We showed that it matches many recently discovered features of both transport and photoemission measurements. Moreover, the study of the topology of the SU(2) field allowed us to properly describe charge modulations, the multiplicity of transitions at the pseudogap temperature, the B-T phase diagram, as well as to predict how to probe experimentally a signature of this theory.

SU(2) theory


Publications

C. Morice, D. Chakraborty, and C. Pépin
Collective mode in the SU(2) theory of cuprates
Phys. Rev. B 98, 224514 (2018)

C. Morice, D. Chakraborty, X. Montiel, and C. Pépin
Pseudo-spin Skyrmions in the Phase Diagram of Cuprate Superconductors
J. Phys.: Condens. Matter 30 (2018) 295601

D. Chakraborty, C. Morice, and C. Pépin
The phase diagram of the underdoped cuprates at high magnetic field
Phys. Rev. B 97, 214501 (2018)

C. Morice, X. Montiel, and C. Pépin
Evolution of spectral and transport quantities with doping in the SU(2) theory of cuprates
Phys. Rev. B 96, 134511 (2017)

Ab-initio study of the bismuth-sulphur family of superconductors

Materials based on bismuth-sulphur layers were found to be superconducting at up to 10 K, as well as exhibiting quantum fluctuations. I probed superconductivity and other phenomena such as magnetism and charge density wave in these materials, using ab-initio techniques such as Density Functional Theory (DFT) and Density Functional Theory for Superconductors (SCDFT).

Highlights of this work include strong evidence for the presence of an unconventional pairing mechanism, the calculation of a magnetic instability in some lanthanide compounds, a prediction of pressure-induced superconductivity and the explanation of the doping mechanism in a stoichiometric material.

BiS superconductor


Publications

C. Morice, R. Akashi, T. Koretsune, S. S. Saxena and R. Arita
Weak phonon-mediated pairing in BiS2 superconductor from first principles
Phys. Rev. B Rapid Comm. 95, 180505(R) (2017)

C. Morice, E. Artacho, S. E. Dutton, H.-J. Kim and S. S. Saxena
Electronic and magnetic properties of superconducting LnO1-xFxBiS2 (Ln = La, Ce, Pr, and Nd) from first principles
J. Phys.: Condens. Matter 28 (2016) 345504

C. Morice, E. Artacho and S. S. Saxena
Electronic structure predictions in Bi-O-S systems
Nov. Supercond. Mater. 1, 75-78 (2015)

T. Sugimoto, D. Ootsuki, C. Morice, E. Artacho, S. S. Saxena, E. F. Schwier, M. Zheng, Y. Kojima, H. Iwasawa, K. Shimada, M. Arita, H. Namatame, M. Taniguchi, M. Takahashi, N. L. Saini, T. Asano, R. Higashinaka, T. D. Matsuda, Y. Aoki, and T. Mizokawa
Fermi surfaces and orbital polarization in superconducting CeO0.5F0.5BiS2 revealed by angle-resolved photoemission spectroscopy
Phys. Rev. B 92, 041113(R) (2015)

C. Morice, E. Artacho, S. E. Dutton, D. Molnar, H.-J. Kim and S. S. Saxena
Effects of stoichiometric doping in superconducting Bi-O-S compounds
J. Phys.: Condens. Matter 27 (2015) 135501



Talks

Invited

  1. University of Amsterdam, November 2019, Amsterdam, The Netherlands

  2. ESPCI, October 2019, Paris, France

  3. Université Paris-Sud, April 2019, Orsay, France

  4. Emergent Phenomena in Strongly Correlated Quantum Matter 2018, Natal, Brazil

  5. International Conference on Superconductivity and Magnetism 2018, Antalya, Turkey

  6. University of Bristol, November 2017, Bristol, United Kingdom

  7. Université de Sherbrooke, September 2017, Sherbrooke, Québec, Canada

  8. Université Paris-Sud, June 2017, Orsay, France

  9. University of Cambridge, March 2017, Cambridge, United Kingdom

  10. University of Amsterdam, May 2016, Amsterdam, The Netherlands

  11. Max Planck Institute of Microstructure Physics, April 2016, Halle, Germany

  12. Jagiellonian University, September 2015, Krakow, Poland

Contributed

  1. Signatures of Topology in Condensed Matter 2019, Trieste, Italy

  2. Strongly Correlated Electron Systems 2017, Prague, Czech Republic

  3. Matériaux, Etats Electroniques, Interactions et Couplages non-Conventionnels 2017, Bordeaux, France

  4. Deutsche Physikalische Gesellschaft Spring Meeting 2015, Berlin, Germany

  5. American Physical Society March Meeting 2015, San Antonio, Texas, USA

  6. Donostia International Conference on Nanoscale Magnetism and Applications 2013, San Sebastian, Spain

Posters

  1. Cutting-Edge Topics in Quantum Materials 2017, Paris, France

  2. Strongly Correlated Electron Systems 2017, Prague, Czech Republic

  3. 10th anniversary of the ERC at Paris-Saclay University, Saclay, France

  4. Gordon Research Conference on Correlated Electron Systems 2016, Mount Holyoke, USA

  5. International Conference on Magnetism 2015, Barcelona, Spain

  6. Strongly Correlated Electron Systems 2014, Grenoble, France

  7. Bernard Coqblin Memorial Symposium 2013, Paris, France

  8. Strongly Correlated Electron Systems 2013, Tokyo, Japan

Contact details

E-mail: corentin.morice@uva.nl