Fault-tolerant parity readout on a shuttling-based trapped-ion quantum computer
Abstract
Quantum error correction requires the detection of errors by reliable measurements of suitable multi-qubit correlation operators. Here, we experimentally demonstrate a fault-tolerant weight-4 parity check measurement scheme. An additional 'flag' qubit serves to detect errors occurring throughout the parity measurement, which would otherwise proliferate into uncorrectable weight-2 errors on the qubit register. We achieve a flag-conditioned parity measurement single-shot fidelity of 93.2(2)\%. Deliberately injecting bit and phase-flip errors, we show that the fault-tolerant protocol is capable of reliably intercepting such faults. For holistic benchmarking of the parity measurement scheme, we use entanglement witnessing to show that the implemented circuit generates genuine six-qubit multi-partite entanglement. The fault-tolerant parity measurement scheme is an essential building block in a broad class of stabilizer quantum error correction protocols, including topological color codes. Our hardware platform is based on atomic ions stored in a segmented microchip ion trap. The qubit register is dynamically reconfigured via shuttling operations, enabling effective full connectivity without operational cross-talk, which provides key capabilities for scalable fault-tolerant quantum computing.
Cite
@article{arxiv.2107.06368,
title = {Fault-tolerant parity readout on a shuttling-based trapped-ion quantum computer},
author = {Janine Hilder and Daniel Pijn and Oleksiy Onishchenko and Alexander Stahl and Maximilian Orth and Björn Lekitsch and Andrea Rodriguez-Blanco and Markus Müller and Ferdinand Schmidt-Kaler and Ulrich Poschinger},
journal= {arXiv preprint arXiv:2107.06368},
year = {2021}
}