Signatures in the Conductance for Phase Transitions in Excitonic Systems

Abstract

We analyse two phase transitions in exciton bilayer systems: a topological phase transition to a phase which hosts Majorana fermions and a phase transition to a Wigner crystal. Using generic simple models for the different phases we discuss the conductance properties of the latter when contacted to metallic leads and demonstrate the possibility to observe the different phase transitions by simple conductance measurements.

Superconductor Hybrids-Electronic Paths to Quantum Computing

“…Identified candidates of this kind are strongly spin-orbit coupled quantum wires proximity coupled to superconductors in a magnetic field [49] [50], exciton condensates proximity coupled to p-wave superconductors [51] and ferromagentic wires proximity coupled to superconductors [52]. The analysis of these system thereby always proceeds via denoting the full Hamiltonian and identifying nontrivial bound states of the system that could represent Majorana fermions.…”

Exciton Condensates and Superconductors-Technical Differences and Physical Similarities

“…The appearance of this phase can be easily observed as the Majorana fermions at the ends of the exciton condensate will open perfectly conducting transmitting channels either through the top or bottom part of the exciton condensate. As the top and bottom part will therefore be perfectly conducting transconductance between the layers has to vanish due to unitarity [9]. The vanishing transconductance is therefore the indicator for the topological phase transition.…”

“…In this short review, we want to provide an overview of the recent advances in the generation of exciton condensates and their phase structure. We will especially focus on the superconductor-like phase [1] which allows to generate topological phases [9]- [11].…”

“…Setup for creation of Majorana fermions in an exciton condensate. The exciton condensate is coupled to four metallic leads and two p-wave superconductors.In this case, the simplest Hamiltonian describing the exciton condensate in the presence of the p-wave superconductors is given by[9] and the τ and σ matrices operate in particle-hole and top-bottom space respectively.…”