Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Universal quantum computation based on nanoscale skyrmion helicity
  qubits in frustrated magnets   Skyrmions in frustrated magnets have the helicity degree of freedom, where
two different configurations of Bloch-type skyrmions are energetically favored
by the magnetic dipole-dipole interaction and characterized by opposite
helicities. A skyrmion must become a quantum-mechanical object when its radius
is of the order of nanometer. We construct a qubit based on the two-fold
degeneracy of the Bloch-type nanoscale skyrmions in frustrated magnets. It is
shown that the universal quantum computation is possible based on nanoscale
skyrmions in a multilayered system. We explicitly show how to construct the
$\pi /4$ phase-shift gate, the Hadamard gate, and the CNOT gate. The one-qubit
quantum gates are materialized by temporally controlling the electric field and
the spin current. The two-qubit gate is materialized with the use of the
Ising-type exchange coupling by controlling the distance between the skyrmion
centers in two adjacent layers. The merit of the present mechanism is that an
external magnetic field is not necessary. Our results may open a possible way
toward universal quantum computations based on nanoscale topological spin
textures.

37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess