Phase boundary of spin-polarized-current state of electrons in bilayer graphene

TL;DR

This paper investigates the phase boundary of the spin-polarized-current state in bilayer graphene using a four-band Hamiltonian, revealing a unique phase boundary with two transition temperatures at finite external voltage.

Contribution

It provides the first detailed analysis of the phase boundary of the spin-polarized-current state in bilayer graphene, including effects of external voltage.

Findings

Identification of phase boundaries with and without external voltage

Discovery of a phase boundary with two transition temperatures at finite voltage

Explanation of the physics behind the unusual phase boundary

Abstract

Using a four-band Hamiltonian, we study the phase boundary of spin-polarized-current state (SPCS) of interacting electrons in bilayer graphene. The model of spin-polarized-current state has previously been shown to resolve a number of experimental puzzles in bilayer graphene. The phase boundaries of the SPCS with and without the external voltage between the two layers are obtained in this work. An unusual phase boundary where there are two transition temperatures for a given carrier concentration is found at finite external voltage. The physics of this phenomenon is explained.