ELFT HÍRADÓ

[tcsaba <tcsaba AT eik.bme.hu>]

                 M E G H Í V Ó - I N V I T A T I O N

    Seminar Series of the Department of Theoretical Physics at the
           Budapest University of Technology and Economics


                           Julia Meyer
                   (Université Grenoble-Alpes)

          Topological multi-terminal Josephson junctions


Topological phases of matter have attracted much interest in recent 
years. Starting with gapped phases such as topological insulators and 
superconductors, more recently gapless topological phases possessing 
topologically protected band crossings have been discovered. Here we 
show that n-terminal Josephson junctions may provide a straightforward 
realization of tunable topological materials in n-1 dimensions, the 
independent superconducting phases playing the role of quasi-momenta. In 
particular, we find Weyl points in the Andreev bound state spectrum of 
4-terminal junctions. The topological properties of the junction may be 
probed experimentally by measuring the transconductance between two 
voltage-biased leads, which we predict to be quantized. Further, the 
analogy between the spectrum of Andreev bound states in an n-terminal 
Jospehson junction and the bandstructure of an n-1-dimensional material 
opens the possibility of realizing topological phases in higher 
dimensions, not accessible in real materials.


Időpont: 2017. november 17. péntek, 10:15
Helyszín: BME Fizikai Intézet, Elméleti Fizika Tanszék,
Budafoki út 8. F-épület, III lépcsőház, szemináriumi szoba