ELFT HÍRADÓ

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

Dear Colleagues, 
 
Next Monday Gergely Zarand will give a talk at the BME Exotic Quantum Phases 
seminar series:
 
Speaker: Gergely Zarand (BME)
Title: "Topologically protected, correlated end spin formation in carbon 
nanotubes"
Time: 14:00 (sharp), June 22 Monday
Location: online, in Teams, see link below

Abstract: "I present the results of a recent work [P. Moca et al, Phys. Rev. 
Lett., in print (arXiv:1909.08400)], where we investigated the formation of 
topological end states in carbon nanotubes, and the role of interactions.  
For most chiralities, semiconducting nanotubes display topologically 
protected end states of multiple degeneracies. We find that the presence of 
Coulomb interactions induces the formation of massive end spins, the close 
analogues of ferromagnetic edge states emerging in graphene nanoribbons.  The 
interaction between the two ends is sensitive to the length of the nanotube, 
its dielectric constant, as well as the size of the end spins: for S=1/2 end 
spins their interaction is antiferromagnetic, while for S>1/2 it changes from 
antiferromagnetic to ferromagnetic with increasing nanotube length. The 
interaction between end spins can be controlled by changing the dielectric 
constant of the environment, thereby providing a possible platform for 
two-spin quantum manipulations.”

The Teams link to join this talk: 
 
https://teams.microsoft.com/l/meetup-join/19%3a4823c4d60bab413294ff022e3a27dda3%40thread.tacv2/1592550938496?context=%7b%22Tid%22%3a%226a3548ab-7570-4271-91a8-58da00697029%22%2c%22Oid%22%3a%22f8b27e90-dbca-4bb5-813c-d6415577ec35%22%7d
 
<https://teams.microsoft.com/l/meetup-join/19%3a4823c4d60bab413294ff022e3a27dda3%40thread.tacv2/1592550938496?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