Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Correlation-Informed Permutation of Qubits for Reducing Ansatz Depth in
  VQE   The Variational Quantum Eigensolver (VQE) is a method of choice to solve the
electronic structure problem for molecules on near-term gate-based quantum
computers. However, the circuit depth is expected to grow significantly with
problem size. Increased depth can both degrade the accuracy of the results and
reduce trainability. In this work, we propose a novel approach to reduce ansatz
circuit depth. Our approach, called PermVQE, adds an additional optimization
loop to VQE that permutes qubits in order to solve for the qubit Hamiltonian
that minimizes long-range correlations in the ground state. The choice of
permutations is based on mutual information, which is a measure of interaction
between electrons in spin-orbitals. Encoding strongly interacting spin-orbitals
into proximal qubits on a quantum chip naturally reduces the circuit depth
needed to prepare the ground state. For representative molecular systems, LiH,
H$_2$, (H$_2$)$_2$, H$_4$, and H$_3^+$, we demonstrate for linear qubit
connectivity that placing entangled qubits in close proximity leads to
shallower depth circuits required to reach a given eigenvalue-eigenvector
accuracy. This approach can be extended to any qubit connectivity and can
significantly reduce the depth required to reach a desired accuracy in VQE.
Moreover, our approach can be applied to other variational quantum algorithms
beyond VQE.

7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys