Carlos Sa de Melo

Professor

Education

Ph.D., Stanford University, 1991

Research

Theoretical condensed matter and ultracold atomic and molecular physics: Superconductors, quantum magnets, superfluids and Bose-Einstein condensates.

My areas of interest include theoretical condensed matter and ultracold atomic and molecular physics. I strongly encourage my students to be broad, deep and creative. Breadth of knowledge is very important in today's physics job market, as is expert (deep) knowledge in a particular area. But most of all the development of new directions, never explored before is the dominant component of my research. Most of my interests are in many body aspects of condensed matter systems (superconductors, quantum magnets, and semiconductors) and atomic/molecular systems (ultracold atoms and molecules). Here is a list of my current research activities:

• Ultracold atoms in the presence of spin-orbit and Zeeman fields
• Topological quantum phase transitions in superfluids and superconductors
• Quantum matter in Abelian and non-Abelian gauge fields
• Multiband superconductivity in Iron superconductors
• Gated two dimensional superconductors: Magic-angle bilayered and trilayered graphene
• Interplay of magnetism and superconductivity
• Quantum phases of ultracold fermions and bosons in optical lattices
• Quantum dipolar systems: molecules and magnetic atoms
• SU(3) Fermions and color-orbit coupling

Papers

SELECTED PUBLICATIONS

1. “Tighter upper bounds on the critical temperature of two-dimensional superfluids and superconductors from the BCS to the Bose regime”, Tingting Shi, Wei Zhang and C. A. R. Sá de Melo, New J. Phys. 26, 093001 (2024).
2. “Evolution from Bardeen-Cooper-Schrieffer to Bose-Einstein Condensation in Two Dimensions: Crossovers and Topological Quantum Phase Transitions”, C. A. R. Sá de Melo and Senne Van Loon, Annu. Rev. Condens. Matter Phys. 15, 109-29 (2024).
3. “Effects of quantum fluctuations in the low-energy collective modes of two-dimensional superfluid Fermi gases from the BCS to the Bose limit", Senne Van Loon and C. A. R. Sá de Melo, Phys. Rev. Lett. 131, 113001 (2023).
4. "Controlling Anderson localization of a Bose-Einstein condensate via spin-orbit coupling and Rabi fields in bichromatic lattices", Bar Alluf and C. A. R. Sá de Melo, Phys. Rev. A 107, 033312 (2023).
5. “Quantum Hall response of SU(3) fermions”, Man Hon Yau and C. A. R. Sá de Melo, Phys. Rev. A 106, 053313 (2022).
6. “Supersolid devil’s staircases of spin-orbit-coupled bosons in optical lattices”, DaisukeYamamoto, Kotaro Bannai, Nobuo Furukawa, and C. A. R. Sá de Melo, Phys. Rev. Res. 4, L032023 (2022).
7. “The evolution from BCS to Bose pairing in two-band superfluids: Quantum phase transitions and crossovers by tuning band offset and interactions, Yue-Ran Shi, Wei Zhang, and C. A. R. Sá de Melo, Eur. Phys. Lett. 139, 36004 (2022).
8. “Density-induced BCS-Bose evolution in gated two-dimensional superconductors: The role of the interaction range in the Berezinskii-Kosterlitz-Thouless transition, Tingting Shi, Wei Zhang, and C. A. R. Sá de Melo, Eur. Phys. Lett. 139, 36003 (2022).
9. “Superfluid transition temperature and fluctuation theory of spin-orbit- and Rabi-coupled fermions with tunable interactions”, Philip D. Powell, Gordon Baym and C. A. R. Sá de Melo, Phys. Rev. A 105, 063304 (2022).
10. “Topological phases and collective modes in U(1) and SU(2) sectors of spin-orbit-coupled two-dimensional Fermi gases”, J. P. A. Devreese, J. Tempere, C. A. R. Sá de Melo, Phys. Rev. A 104, 033304 (2022).
11. “SU(3) versus SU(2) fermions in optical lattices: color-Hall versus spin-Hall insulators”, Man Hon Yau and C. A. R. Sá de Melo, Eur. Phys. Lett. 135, 16001 (2021).
12. “Eigenspectrum, Chern Numbers and Phase Diagrams of Ultracold Color-orbit Coupled SU(3) Fermions in Optical Lattices”, Man Hon Yau and C. A. R. Sá de Melo, Phys. Rev. A 103, 043302 (2021).
13. "Nematic-Orbit Coupling and Nematic Density Waves in Spin-1 Condensates", Di Lao, Chandra Raman , and C. A. R. Sá de Melo, Phys. Rev. Lett. 124, 173203 (2020).
14. "Enhanced transport of spin-orbit-coupled Bose gases in disordered potentials", Y. Yue,  C. A. R. Sá de Melo, and I. B. Spielman, Phys. Rev. A 102, 033325 (2020).
15. "Chern-number spectrum of ultracold fermions in optical lattices tuned independently via artificial magnetic, Zeeman, and spin-orbit fields", Man Hon Yau and C. A. R. Sá de Melo, Phys. Rev. A 99, 043625 (2019).
16. "Staircase in magnetization and entanglement entropy of spinor condensates", H. M. Bharath, M. S. Chapman, and C. A. R. Sá de Melo, Phys.  Rev. A 98, 031601(R) (2018).
17. "Color superfluidity of neutral ultracold fermions in the presence of color-flip and color-orbit fields", Doga Murat Kurkcuoglu and C. A. R. Sá de Melo, Phys. Rev. A 97, 023632 (2018).
18. "Quantum phases of two-component bosons with spin-orbit coupling in optical lattices", Daisuke Yamamoto, I. B. Spielman, and C. A. R. Sá de Melo, Phys. Rev. A 96, 061603(R) (2017).
19. "Formation of Feshbach molecules in the presence of artificial spin-orbit coupling and Zeeman fields", Doga Murat Kurkcuoglu and C. A. R. Sá de Melo, Phys. Rev. A 93, 023611 (2016).
20. "Quantum phase transitions and Berezinskii-Kosterlitz-Thouless temperature in a two-dimensional spin-orbit-coupled Fermi gas", Jeroen P. A. Devreese, Jacques Tempere, and C. A. R. Sá de Melo, Phys. Rev. A 92, 043618 (2015).
21. “Effects of spin-orbit coupling on the Berezinskii-Kosterlitz-Thouless transition and the vortex-antivortex structure in two-dimensional Fermi gases”, J. P. A. Devresse, J. Tempere and C. A. R. Sá de Melo, Phys. Rev. Lett. 113, 165305  (2014).
22. “Antiferromagnetic spatial ordering in a quenched one-dimensional spinor gas”, A. Vinit, E. M. Bookjans, C. A. R. Sá de Melo, and C. Raman, Phys. Rev. Lett. 110, 165301 (2013).
23. “Emergence of Majorana and Dirac particles in ultracold fermions via tunable interactions, spin-orbit effects, and Zeeman fields”,  Kangjun Seo, Li Han, and C. A. R. Sá de Melo, Phys. Rev. Lett. 109, 105303 (2012).
24. “Dipolar bosons in triangular optical lattices: quantum phase transitions and anomalous hysteresis”, D. Yamamoto, I. Danshita, and C. A. R. Sá de Melo, Phys. Rev. A 85, 021601(R) (2012).
25. “Evolution from BCS to Berezinskii-Kosterlitz-Thouless superfluidity in one-dimensional optical lattices”, M. Iskin, and C. A. R. Sá de Melo, Phys. Rev. Lett. 103, 165301 (2009).
26. “Stability of superfluid and supersolid phases of dipolar bosons in optical lattices”, I. Danshita, and C. A. R. Sá de Melo, Phys. Rev. Lett. 103, 225301 (2009).