Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Interplay of Magnetic Order, Pairing and Phase Separation in a One
  Dimensional Spin Fermion Model   We consider a lattice model of itinerant electrons coupled to an array of
localized classical Heisenberg spins. The nature of the ground state ordered
magnetic phases that result from the indirect spin-spin coupling mediated by
the electrons is determined as a function of density and the spin-fermion
coupling $J$. At a fixed chemical potential, spiral phases exist only up to
values of $J$ which are less than roughly half the electronic bandwidth. At a
fixed electron density and near half filling, the system phase separates into a
half-filled antiferromagnetic phase and a spiral phase. The ferromagnetic
phases are shown to be fully polarized, while the spiral phases have equal
admixture of up and down spins. Phase separation survives in the presence of
weak pairing field $\Delta$ but disappears when $\Delta$ exceeds a critical
value $\Delta_c$. If pairing fields are large enough, an additional spiral
state arises at strong coupling $J$. The relevance of this study, especially
the phase separation, to artificially engineered systems of adjacent itinerant
electrons and localized spins is discussed. In particular, we propose a method
which might allow for the braiding of Majorana fermions by changing the density
and moving their location as they are pulled along by a phase separation
boundary.

0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga