Professor Comin’s research explores the novel phases of matter that can be found in electronic solids with strong interactions, also known as quantum materials. In these systems, the interplay between different degrees of freedom – charge, spin, orbital, and lattice – leads to new flavors of emergent orders via the mechanism of electronic symmetry breaking. These phenomena include, among others: superconductivity, (anti)ferromagnetism, spin-density-waves, charge order, ferroelectricity, orbital order, and any combination thereof.
Our group uses a combination of synthesis, scattering, and spectroscopy in order to obtain a comprehensive picture of these intriguing phenomena.
Photon scattering techniques represent one of the most effective toolsets to study and characterize symmetry breaking phenomena in solids. Among these, resonant X-ray scattering has the ability to reveal the spatial ordering of the spin/charge/orbital degrees of freedom, which is of primary relevance for the study of broken symmetries in quantum materials. We complement the X-ray work with table-top optical probes (Raman scattering and Kerr/Faraday effect) to study these phenomena and their spectroscopic signatures in the extended phase diagram — as a function of temperature, pressure, strain, and magnetic fields.
We additionally use angle-resolved photoemission spectroscopy (ARPES) to measure the energy-momentum spectrum of single-particle excitations in strongly-correlated electron systems and topological electronic materials. In the latter, our ARPES studies are focused on elucidating the source of Berry curvature in the electronic band structure of topological metals and semimetals realized from novel lattice geometries (collaboration with Joe Checkelsky).
On the synthesis front, we focus on the growth of van der Waals materials characterized by moderate to strong electronic correlations leading to broken symmetry phases including charge-density-waves and various forms of magnetic order. We seek to elucidate how these emergent collective orders evolve from the 3D (bulk) to the 2D (monolayer) limit, and as a function of carrier doping, in these exfoliable crystals.
The quantum materials we like to explore include transition metal oxides (high-temperature superconductivity, spin-orbit entanglement, multiferroicity, etc.), rare earth compounds, and topological insulators. We study single-crystalline materials, as well as thin films and heterointerfaces.
Riccardo Comin joined MIT as an Assistant Professor of Physics in July 2016. He completed his undergraduate studies at the Universita’ degli Studi di Trieste in Italy, where he also obtained a M.Sc. in Physics in 2009. Later, he pursued doctoral studies at the University of British Columbia, Canada, earning a PhD in 2013. Since 2014 he is an NSERC postdoctoral fellow at the University of Toronto.
For his work using synchrotron-based x-ray scattering methods on quantum materials and electrically-tuned optoelectronic materials, he was recently selected as recipient of the Bancroft Thesis Award (2014), Fonda-Fasella Award (2014), John Charles Polanyi Prize in Physics (2015), McMillan Award (2015), and Bryan R. Coles prize (2016).
The findings could lead to faster, more secure memory storage, in the form of antiferromagnetic bits.
Awards & Honors
- 2021 // DOE Office of Science Early Career Research Program Award
- 2019 // Class of 1947 Career Development Professor
- 2018 // U.S. Air Force Young Investigator Research Program (AFOSR) Research Grant
- 2018 // Alfred P. Sloan Research Fellowship
- 2017 // CLS Young Investigator Award
- 2016 // Bryan R. Coles Prize
- 2015 // McMillan Award
- 2015 // John Charles Polanyi Prize in Physics
- 2014 // Fonda-Fasella Award
- 2014 // G. Bancroft Ph.D. Thesis Award
M. Kang†, L. Ye†, S. Fang, J.-S. You, A. Levitan, M. Han, J. I. Facio, C. Jozwiak, A. Bostwick, E. Rotenberg, M. K. Chan, R. D. McDonald, D. Graf, K. Kaznatcheev, E. Vescovo, D. C. Bell, E. Kaxiras, J. van den Brink, M. Richter, M. P. Ghimire, J. G. Checkelsky†, R. Comin†. Dirac fermions and flat bands in the ideal kagome metal FeSn. Nature Materials, 19, 163 (2020). DOI:10.1038/s41563-019-0531-0
J. Li, J. Pelliciari, C. Mazzoli, S. Catalano, F. Simmons, J. T. Sadowski, A. Levitan, M. Gibert, E. Carlson, J.-M. Triscone, S. Wilkins, R. Comin. Scale-invariant magnetic textures in the strongly correlated oxide NdNiO3, Nature Communications 10, 4568 (2019). DOI: 0.1038/s41467-019-12502-0
M. Kang, J. Pelliciari, A. Frano, N. Breznay, E. Schierle, E. Weschke, R. Sutarto, F. He, P. Shafer, E. Arenholz, M. Chen, K. Zhang, A. Ruiz, Z. Hao, S. Lewin, J. Analytis, Y. Krockenberger, H. Yamamoto, T. Das, R. Comin. Evolution of charge order topology across a magnetic phase transition in cuprate superconductors, Nature Physics 15, 335 (2019). DOI: 10.1038/s41567-018-0401-8