ELFT HÍRADÓ

[Andras Palyi <palyi AT mail.bme.hu>]

Dear Colleagues, 

Next Monday, the BME Exotic Quantum Phases seminar series continues with this 
talk:

Speaker: Ion Cosma Fulga (IFW Dresden)
Title: Triple point fermions in a minimal symmorphic model
Abstract: see below
Time: Nov 16, Monday 14:15
Location: online in Teams

About the speaker: Cosma is a theoretical physicist working at the interface 
of condensed-matter physics, topology, quantum transport and quantum 
information. Cosma did his PhD research in Leiden, The Netherlands, in the 
group of Carlo Beenakker, and then he was a postdoc with Ady Stern at the 
Weizmann Institute (Rehovot, Israel). Currently, he is a tenured junior group 
leader at IFW Dresden in Germany. 

Link to join the seminar in Teams:
https://teams.microsoft.com/l/meetup-join/19%3abc62e547060d4dbead491ee4b995f5f9%40thread.tacv2/1605191809988?context=%7b%22Tid%22%3a%226a3548ab-7570-4271-91a8-58da00697029%22%2c%22Oid%22%3a%22f8b27e90-dbca-4bb5-813c-d6415577ec35%22%7d

Best regards,
Andras Palyi 

= = = 

Abstract: 
Gapless topological phases of matter may host emergent quasiparticle 
excitations which
have no analog in quantum field theory. This is the case of so called triple 
point fermions
(TPF), quasiparticle excitations protected by crystal symmetries, which show 
fermionic
statistics but have an integer (pseudo)spin degree of freedom. TPFs have been 
predicted in
certain three-dimensional non-symmorphic crystals, where they are pinned to 
high
symmetry points of the Brillouin zone. In this work, we introduce a minimal, 
three-band
model which hosts TPFs protected only by the combination of a C4 rotation and 
an anti-
commuting mirror symmetry. Unlike current non-symmorphic realizations, our 
model
allows for TPFs which are anisotropic and can be created or annihilated 
pairwise. It
provides a simple, numerically affordable platform for their study.