About

Concentration:

Theoretical Condensed Matter Physics

Interests:

We study a variety of problems in theoretical condensed matter physics, ranging from magnetism to topological matter. Modern magnetism is dedicated to understanding magnetic properties that originate from the spin degree of freedom of electrons and its interaction with electromagnetic fields. Topological matter is another attractive field of contemporary condensed matter physics, in which the notion of Berry phase (in either real or momentum space) is adopted to define topological phases of matter protected by symmetry. As magnetism meets topology in quantum materials, it is interesting to explore the coupled transport of spin, charge and heat in topological states of quantum matter.  Aside from fundamental interests, our research can lead to new devices for spin-based electronics and quantum computation. Currently, our research topics include:

• Coupled spin and charge transport in topological quantum materials (e.g, topological insulators, topological semimetals etc.) arising from spin-orbit and many-body interactions;
• Magnetotransport in hybrid magnetic, organic, and oxide structures;
• Magnetization dynamics and magnon transport in ferromagnetic/antiferromagnetic materials and their heterostructures;
• Stability and dynamics of magnetic skyrmions as well as skyrmion-induced charge transport (e.g., topological Hall effect);
• Chiral surface/edge magnetoplasmons associated with Berry phase effects.

Our group has engaged in a number of collaborations with both theorists and experimentalists around the world, including researchers at National University of Singapore, University of Waterloo, Fudan University, University of Hong Kong, University of Geneva, University of Tokyo, Stanford University, UIUC, Argonne National Laboratory etc.  We are also collaborating interactively with the CATS center (an Energy Frontier Research Center funded by DOE) which aims at advancing our understanding and accelerating breakthrough innovations in topological semimetals.

Students (both undergraduates and graduates) and postdocs with passions in the research field of condensed matter theory are encouraged to join our group. Please contact Prof. Shulei Zhang if interested.

Publications

A more complete list of my publications can be found on Google Scholar.

Pan He*, Steven S.-L. Zhang*, Dapeng Zhu, Shuyuan Shi, Jiawei Yu, Olle Heinonen, Giovanni Vignale and Hyunsoo Yang, “Nonlinear planar Hall effect”, Phys. Rev. Letts. 123, 016801 (2019). *Contributed equally.

Steven S.-L. Zhang and Giovanni Vignale, “Chiral surface and edge plasmons in ferromagnetic conductors”, Phys. Rev. B 97, 224408 (2018).

Pan He*, Steven S.-L. Zhang*, Dapeng Zhu, Yang Liu, Yi Wang, Jiawei Yu, Giovanni Vignale, Hyunsoo Yang, “Bilinear magneto-electric resistance as a probe of three-dimensional spin texture in topological surface states”, Nature Physics 14, 495–499 (2018). *Contributed equally.

Steven S.-L. Zhang and Olle G. Heinonen, “Topological Hall effect in diffusive ferromagnetic thin films with spin-flip scattering”, Phys. Rev. B 97, 134401 (2018).

Steven S.-L. Zhang, Charudatta Phatak, Amanda Petford-Long and Olle Heinonen, “Tailoring Magnetic Skyrmions by Geometric Confinement of Magnetic Structures”, Appl. Phys. Lett. 111, 242405 (2017). Editor’s Pick.

Steven S.-L. Zhang, Ezio Iacocca, Olle Heinonen, “Tunable mode coupling in nano-contact spin torque oscillators”, Phys. Rev. Applied 8, 014034 (2017).

Steven S.-L. Zhang and Giovanni Vignale, “Nonlocal anomalous Hall effect”, Phys. Rev. Lett. 116 (13), 136601(2016).

Steven S.-L. Zhang and Giovanni Vignale, “Theory of unidirectional spin Hall magnetoresistance in heavy-metal/ferromagnetic-metal bilayers”, Phys. Rev. B 94 140411(R) (2016). Rapid Communication.

Steven S.-L. Zhang, Giovanni Vignale and Shufeng Zhang, “Anisotropic magnetoresistance driven by surface spin orbit scattering”, Phys. Rev. B 92, 024412 (2015).

Steven S.-L. Zhang and Shufeng Zhang, “Spin convertance at magnetic interfaces”, Phys. Rev. B 86, 214424 (2012).

Steven S.-L. Zhang and Shufeng Zhang, “Magnon mediated electric current drag across a ferromagnetic insulator layer”, Phys. Rev. Lett. 109, 096603 (2012).

Shufeng Zhang and Steven S.-L. Zhang, “Generalization of the Landau-Lifshitz-Gilbert equation for conducting ferromagnets”, Phys. Rev. Lett. 102, 086601 (2009). Editor’s Suggestion.