Benjamin Béri - Research Interests

Möbius strip
Möbius strip analogy of topological phases: inspecting local details of the strip won't reveal anything strange; the object as a whole, however, has a twist − it is topologically nontrivial. (Photo by David Benbennick - CC:BY-SA.)

My research is on quantum matter, with a current focus on so-called topological phases: these are systems displaying a strange kind of order that has no local order parameter (like magnetisation is for ferromagnets), but which appears through topological invariants (like the twist of the strip on the right), manifested in features such as boundary modes, ground state degeneracy, or emergent particles with exotic braiding statistics ("anyons"). Due to their topological nature, these features are insensitive to local details, and hence to most perturbations. This has various technological ramifications, ranging from existing applications (e.g., the quantum Hall resistance standard) to intriguing perspectives such as topological quantum computation.

My present interests in this area include:

  • novel topological phases emerging from strong interactions, in particular new phases related to topological insulators;
  • novel strong correlation effects that arise if conventional materials are coupled to topological phases, in particular to systems with Majorana fermions, non-abelian anyons studied in ongoing experiments.

For more information on my research, please see my publications.