Abstract
On the basis of the quantum Zeno effect, it has been recently shown [D. K. Burgarth, Nat. Commun. 5, 5173 (2014)2041-172310.1038/ncomms6173] that a strong-amplitude-damping process applied locally on a part of a quantum system can have a beneficial effect on the dynamics of the remaining part of the system. Quantum operations that cannot be implemented without the dissipation become achievable by the action of the strong dissipative process. Here we generalize this idea by identifying decoherence-free subspaces (DFSs) as the subspaces in which the dynamics becomes more complex. Applying methods from quantum control theory, we characterize the set of reachable operations within the DFSs. We provide three examples that become fully controllable within the DFSs while the control over the original Hilbert space in the absence of dissipation is trivial. In particular, we show that the (classical) Ising Hamiltonian is turned into a Heisenberg Hamiltonian by strong collective decoherence, which provides universal quantum computation within the DFSs. Moreover, we perform numerical gate optimization to study how the process fidelity scales with the noise strength. As a by-product, a subsystem fidelity that can be applied in other optimization problems for open quantum systems is developed.
| Original language | English |
|---|---|
| Article number | 062308 |
| Journal | Physical Review A - Atomic, Molecular, and Optical Physics |
| Volume | 93 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - 2016 Jun 6 |
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ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
Cite this
Universal control induced by noise. / Arenz, Christian; Burgarth, Daniel; Facchi, Paolo; Giovannetti, Vittorio; Nakazato, Hiromichi; Pascazio, Saverio; Yuasa, Kazuya.
In: Physical Review A - Atomic, Molecular, and Optical Physics, Vol. 93, No. 6, 062308, 06.06.2016.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Universal control induced by noise
AU - Arenz, Christian
AU - Burgarth, Daniel
AU - Facchi, Paolo
AU - Giovannetti, Vittorio
AU - Nakazato, Hiromichi
AU - Pascazio, Saverio
AU - Yuasa, Kazuya
PY - 2016/6/6
Y1 - 2016/6/6
N2 - On the basis of the quantum Zeno effect, it has been recently shown [D. K. Burgarth, Nat. Commun. 5, 5173 (2014)2041-172310.1038/ncomms6173] that a strong-amplitude-damping process applied locally on a part of a quantum system can have a beneficial effect on the dynamics of the remaining part of the system. Quantum operations that cannot be implemented without the dissipation become achievable by the action of the strong dissipative process. Here we generalize this idea by identifying decoherence-free subspaces (DFSs) as the subspaces in which the dynamics becomes more complex. Applying methods from quantum control theory, we characterize the set of reachable operations within the DFSs. We provide three examples that become fully controllable within the DFSs while the control over the original Hilbert space in the absence of dissipation is trivial. In particular, we show that the (classical) Ising Hamiltonian is turned into a Heisenberg Hamiltonian by strong collective decoherence, which provides universal quantum computation within the DFSs. Moreover, we perform numerical gate optimization to study how the process fidelity scales with the noise strength. As a by-product, a subsystem fidelity that can be applied in other optimization problems for open quantum systems is developed.
AB - On the basis of the quantum Zeno effect, it has been recently shown [D. K. Burgarth, Nat. Commun. 5, 5173 (2014)2041-172310.1038/ncomms6173] that a strong-amplitude-damping process applied locally on a part of a quantum system can have a beneficial effect on the dynamics of the remaining part of the system. Quantum operations that cannot be implemented without the dissipation become achievable by the action of the strong dissipative process. Here we generalize this idea by identifying decoherence-free subspaces (DFSs) as the subspaces in which the dynamics becomes more complex. Applying methods from quantum control theory, we characterize the set of reachable operations within the DFSs. We provide three examples that become fully controllable within the DFSs while the control over the original Hilbert space in the absence of dissipation is trivial. In particular, we show that the (classical) Ising Hamiltonian is turned into a Heisenberg Hamiltonian by strong collective decoherence, which provides universal quantum computation within the DFSs. Moreover, we perform numerical gate optimization to study how the process fidelity scales with the noise strength. As a by-product, a subsystem fidelity that can be applied in other optimization problems for open quantum systems is developed.
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UR - http://www.scopus.com/inward/citedby.url?scp=84973655811&partnerID=8YFLogxK
U2 - 10.1103/PhysRevA.93.062308
DO - 10.1103/PhysRevA.93.062308
M3 - Article
AN - SCOPUS:84973655811
VL - 93
JO - Physical Review A
JF - Physical Review A
SN - 2469-9926
IS - 6
M1 - 062308
ER -