Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Crossover between Strongly-coupled and Weakly-coupled Exciton
  Superfluids   In fermionic systems, superconductivity and superfluidity are enabled through
the condensation of fermion pairs. The nature of this condensate can be tuned
by varying the pairing strength, with weak coupling yielding a BCS-like
condensate and strong coupling resulting in a BEC-like process. However,
demonstration of this cross-over has remained elusive in electronic systems.
Here we study graphene double-layers separated by an atomically thin insulator.
Under applied magnetic field, electrons and holes couple across the barrier to
form bound magneto-excitons whose pairing strength can be continuously tuned by
varying the effective layer separation. Using temperature-dependent Coulomb
drag and counter-flow current measurements, we demonstrate the capability to
tune the magneto-exciton condensate through the entire weak-coupling to
strong-coupling phase diagram. Our results establish magneto-exciton
condensates in graphene as a model platform to study the crossover between two
Bosonic quantum condensate phases in a solid state system.

27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol