Abstract
Fast and reliable reset of a qubit is a key prerequisite for any quantum technology. For real world open quantum systems undergoing non-Markovian dynamics, reset implies not only purification, but in particular erasure of initial correlations between qubit and environment. Here, we derive optimal reset protocols using a combination of geometric and numerical control theory. For factorizing initial states, we find a lower limit for the entropy reduction of the qubit as well as a speed limit. The time-optimal solution is determined by the maximum coupling strength. Initial correlations, remarkably, allow for faster reset and smaller errors. Entanglement is not necessary.
Original language | English |
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Article number | 113042 |
Pages (from-to) | 1-16 |
Journal | New Journal of Physics |
Volume | 19 |
Issue number | 11 |
DOIs | |
Publication status | Published - 1 Nov 2017 |
MoE publication type | A1 Journal article-refereed |
Keywords
- quantum control
- state preparation
- superconducting qubits