Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Evidence for a spinon Fermi surface in a triangular lattice quantum spin
  liquid candidate   A quantum spin liquid is an exotic quantum state of matter in which spins are
highly entangled and remain disordered down to zero temperature. Such a state
of matter is potentially relevant to high-temperature superconductivity and
quantum-information applications, and experimental identification of a quantum
spin liquid state is of fundamental importance for our understanding of quantum
matter. Theoretical studies have proposed various quantum-spin-liquid ground
states, most of which are characterized by exotic spin excitations with
fractional quantum numbers (termed `spinon'). Here, we report neutron
scattering measurements that reveal broad spin excitations covering a wide
region of the Brillouin zone in a triangular antiferromagnet YbMgGaO4. The
observed diffusive spin excitation persists at the lowest measured energy and
shows a clear upper excitation edge, which is consistent with the particle-hole
excitation of a spinon Fermi surface. Our results therefore point to a QSL
state with a spinon Fermi surface in YbMgGaO4 that has a perfect spin-1/2
triangular lattice as in the original proposal of quantum spin liquids.

27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph