Publications and preprints

Superconductivity, electronic correlations and collective modes in graphene multilayers

Investigation of correlated phases, superconductivity and collective modes in twisted (moiré) and untwisted (rhombohedral) graphene multilayers. Signatures in various experimental probes and potential to realize gate-defined quantum devices.

(Primarily) theory works:

• Trigonal warping enables linear optical spectroscopy in single-valley superconductors. Benjamin Levitan and ÉLH, arXiv:2508.09387  

• Symmetry-broken metallic orders in spin-orbit-coupled Bernal bilayer graphene. Jin Min Koh, Alex Thomson, Jason Alicea and ÉLH, Phys. Rev. B 110, 245118 (2024) -- Editor's suggestion.

• Superconductivity from spin-canting fluctuations in rhombohedral graphene. Zhiyu Dong, ÉLH and Jason Alicea, arXiv:2406.17036 

• Correlated phases in spin-orbit coupled rhombohedral trilayer graphene. Jin Ming Koh, Jason Alicea and ÉLH, Phys. Rev. B 109, 035113 (2024)

• Gate-defined topological Josephson junctions in Bernal bilayer graphene. Ying-Ming Xie, ÉLH, Andrea F. Young, Stevan Nadj-Perge, Jason Alicea, Phys. Rev. Lett. 131, 146601 (2023) -- Editor's suggestion.

• Andreev reflection spectroscopy in strongly-paired superconductors. Cyprian Lewandowski, ÉLH, Alex Thomson, Stevan Nadj-Perge and Jason Alicea. Phys. Rev. B (Letter)  107, L020502 (2023). -- Editor's suggestion.

Experimental collaborations:

• Superconductivity and spin canting in spin-orbit proximitized rhombohedral trilayer graphene. Caitlin Patterson, Owen Sheekey, Trevor Arp, ..., ÉLH, Jason Alicea, and Andrea F. Young,  Nature  641, 632–638 (2025) 

• Imaging inter-valley coherent order in twisted trilayer graphene. Hyunjin Kim, Younjoon Choi, ÉLH, et al. Nature 623, 942-948 (2023)

• Enhanced superconductivity in spin-orbit proximitized Bernal bilayer graphene. Yiran Zhang, Robert Polski, Alex Thomson, ÉLH, et al. Nature 613, 268-273 (2023)

Twisted high-temperature superconductors

Realizing topological superconductivity at high temperatures based on twisted two-dimensional nodal superconductors (such as cuprate films).

• Josephson diode effects in twisted nodal superconductors. Pavel Volkov, ÉLH, Tarun Tummuru, Stephan Plugge, Jed Pixley and Marcel Franz, Phys. Rev. B 109, 094518 (2024).

• Twisted multilayer nodal superconductors. Tarun Tummuru, ÉLH and Marcel Franz. Phys Rev. B 106, 014520 (2022).

Topology and geometry in quasi-periodically driven systems

Connection between quantum geometry and dissipation in quasi-periodically driven quantum systems hosting topological frequency conversion, and physical  realizations in graphene multilayers.

• Topological frequency conversion in rhombohedral graphene multilayers. ÉLH, Iliya Esin, Gil Refael and Frederik Nathan, Phys. Rev. B (Letter) 110, L100305 (2024)

• Quantum geometry and bounds on dissipation in slowly driven quantum systems. Iliya Esin, ÉLH, Frederik Nathan and Gil Refael, Phys. Rev. Lett 134, 146603 (2025).

Holographic quantum matter and quantum chaos

Exploration of toy models for non-Fermi liquids with holographic duals, their potential realizations in condensed matter systems, as well as new protocols for measuring out-of-time-order correlators in quantum many-body systems.

•   Superconducting instabilities in a spinful SYK model. ÉLH, Sharmistha Sahoo and Marcel Franz, Phys. Rev. B (Letter) 104 L020509 (2021)

• Traversable wormhole and Hawking-Page transition in coupled complex SYK models. Sharmistha Sahoo,  ÉLH, Stephan Plugge and Marcel Franz, Phys. Rev. Research 2, 043049 (2020) -- Editor's Suggestion.

• Revival dynamics in a traversable wormhole. Stephan Plugge, ÉLH and Marcel Franz, Phys. Rev. Lett. 124, 221601 (2020)

•  Diagnosing quantum chaos in many-body systems using entanglement as a resource. ÉLH, Stephan Plugge, Oguzhan Can and Marcel Franz, Phys. Rev. Research 2, 013254 (2020)

• Family of Sachdev-Ye-Kitaev models motivated by experimental considerations. ÉLH, Chengshu Li and Marcel Franz. Phys. Rev. B 97, 235124 (2018)

Strain-induced gauge fields in graphene

Physics of strain-induced Landau levels in graphene, and its experimental signatures.

• Dispersive Landau levels and valley currents in strained graphene nanoribbons. ÉLH, Xiao-Xiao Zhang and Marcel Franz, Phys. Rev. B 101, 085423 (2020).

• Room temperature strain-induced Landau levels in graphene on a wafer-scale platform. P. Nigge, A. C. Qu, ÉLH, et al.   Science Advances 5, eaaw5593 (2019).

Spin liquid phases in geometrically frustrated magnets

Understanding the response of quantum and classical spin ice materials to boundary effects and electric fields.

• Spin ice thin films: Large-N theory and Monte Carlo simulations. ÉLH, Jeffrey G. Rau and Michel J. P. Gingras, Phys. Rev. X 8, 02153 (2018).

• Electric field control of emergent electrodynamics in quantum spin ice. ÉLH, Subhro Bhattacharjee and Roderich Moessner, Phys. Rev. B 96, 125145 (2017).

Other works:

• News & Views: Topology in Abundance. ÉLH and Marcel Franz, Nature Reviews Physics 1, 183 (2019).

• Supersymmetry in an interacting Majorana model on the kagome lattice. Chengshu Li, ÉLH and Marcel Franz, Phys. Rev. B 100, 195146 (2019).

• Shape dependence of two-cylinder Renyi entropies for free bosons on a lattice. Leilee Chojnacki, Caleb Q. Cook, Denis Dalidovich, Lauren E. Hayward Sierens, ÉLH, Roger G. Melko and Tiffany F. Vlaar, Phys. Rev. B 94, 165136 (2016).

• Dynamical and anharmonic effects on the electron-phonon coupling and the zero-point renormalization of the electronic structure. Gabriel Antonius, Samuel Poncé, ÉLH, Gabriel Auclair, Xavier Gonze and Michel Côté, Phys. Rev. B 92, 085137 (2015)