Talk given by

Prof.  Dr. Anton Akhmerov
Kavli institute of nanoscience 
TU Delft
Delft, The Netherlands

Abstract: 

Semiconducting nanowires brought into contact with a
superconductor and subjected to an external magnetic field are one of
the two actively explored paths to creating Majoranas. Beautifully,
many physical phenomena occurring in these systems are captured by a
simple model containing only a single one-dimensional spinful electron
mode. However, while being amazingly useful for developing a basic
understanding of the system, this model can also be misleading because
of failing to capture several phenomena crucial for predicting the
properties of Majoranas. I will discuss two examples of such
phenomena: the orbital effect of magnetic field and the effect of
strong coupling to the superconductor. While the physical system beyond 1D
is too complex to be treatable analytically, I will use simple estimates and
symmetry analysis to build up the intuition about the phenomena we are studying.