Abstract
The Gottesman–Kitaev–Preskill encoding of a qubit in a harmonic oscillator is a promising building block towards fault-tolerant quantum computation. Recently, this encoding was experimentally demonstrated for the first time in trapped-ion and superconducting circuit systems. However, these systems lack some of the Gaussian operations which are critical to efficiently manipulate the encoded qubits. In particular, homodyne detection, which is the go-to method for efficient readout of the encoded qubit in the vast majority of theoretical work, is not readily available, heavily limiting the readout fidelity. Here, we present an alternative read-out strategy designed for qubit-coupled systems. Our method can improve the readout fidelity with several orders of magnitude for such systems and, surprisingly, even surpass the fidelity of homodyne detection in the low squeezing regime.
Original language | English |
---|---|
Article number | 035016 |
Journal | Quantum Science and Technology |
Volume | 6 |
Issue number | 3 |
Number of pages | 9 |
DOIs | |
Publication status | Published - 2021 |
Keywords
- Bosonic codes
- Gottesman–Kitaev–Preskill states
- Quantum error correction
- Superconducting qubits
- Trapped ions