Superfast encodings for fermionic quantum simulation
Oct 18, 2019
8 pages
Published in:
- Phys.Rev.Res. 1 (2019) 3, 033033
- Published: Oct 18, 2019
Citations per year
Abstract: (APS)
Simulation of fermionic many-body systems on a quantum computer requires a suitable encoding of fermionic
degrees of freedom into qubits. Here we revisit the superfast encoding introduced by Kitaev and one of the
authors. This encoding maps a target fermionic Hamiltonian with two-body interactions on a graph of degree
d to a qubit simulator Hamiltonian composed of Pauli operators of weight O(d). A system of m Fermi modes
gets mapped to n = O(md) qubits. We propose generalized superfast encodings (GSEs) which require the same
number of qubits as the original one but have more favorable properties. First, we describe a GSE such that
the corresponding quantum code corrects any single-qubit error provided that the interaction graph has degree
d 6. In contrast, we prove that the original superfast encoding lacks the error correction property for d 6.
Second, we describe a GSE that reduces the Pauli weight of the simulator Hamiltonian from O(d) to O(log d).
The robustness against errors and a simplified structure of the simulator Hamiltonian offered by GSEs can make
simulation of fermionic systems within the reach of near-term quantum devices. As an example, we apply the
new encoding to the fermionic Hubbard model on a 2D lattice.- Quantum Information, Science & Technology
- Quantum algorithms
- Quantum error correction
- Quantum simulation
- quantum simulation
- fermion
- qubit
- Hamiltonian
- quantum error correction
- quantum information
References(21)
Figures(0)