Topological superconductivity and Majorana fermions in the heterostructure of EuS island and planar gold surface

In a recent work [1], possible signatures of a pair of Majorana zero-energy modes were found
within the platform forming by EuS island and gold wire. In this work, we show the gold wire can
be replaced by a large gold surface in this platform. Furthermore, we found the chemical potential
step between the EuS island covering region and bare gold surface region are essential for keeping
a sizable topological region in the large gold surface case. Our results suggest the feasibility of
depositing EuS wires on a large area of gold and simplify the fabrication process further.

[1] S. Manna, P. Wei, Y. Xie, K. T. Law, P. A. Lee, and
J. Moodera, in press.