Year: 2020
Type: article
Abstract: An outstanding challenge for quantum information processing using bosonic systems is Gaussian errors such as excitation loss and added thermal noise errors. Thus, bosonic quantum error correction is essential. Most bosonic quantum error correction schemes encode a finite-dimensional logical qubit or qudit into noisy bosonic oscillator modes. In this case, however, the infinite-dimensional bosonic nature of the physical system is lost at the error-corrected logical level. On the other hand, there are several proposals for encoding an oscillator mode into many noisy oscillator modes. However, these oscillator-into-oscillators encoding schemes are in the class of Gaussian quantum error correction. Therefore, these codes cannot correct practically relevant Gaussian errors due to the established no-go theorems that state that Gaussian errors cannot be corrected by using only Gaussian resources. Here, we circumvent these no-go results and show that it is possible to correct Gaussian errors by using Gottesman-Kitaev-Preskill (GKP) states as non-Gaussian resources. In particular, we propose a non-Gaussian oscillator-into-oscillators code, namely the GKP two-mode squeezing code, and demonstrate that it can quadratically suppress additive Gaussian noise errors in both the position and momentum quadratures except for a small sublogarithmic correction. Furthermore, we demonstrate that our GKP two-mode squeezing code is near optimal in the weak noise limit by proving via quantum information theoretic tools that quadratic noise suppression is optimal when we use two physical oscillator modes. Lastly, we show that our non-Gaussian oscillator encoding scheme can also be used to correct excitation loss and thermal noise errors, which are dominant error sources in many realistic bosonic systems.
Source: Physical Review Letters
Authors: Kyungjoo Noh, S. M. Girvin, Liang Jiang
Institutions: Yale University, University of Chicago
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: green
Awards: G1482135624, G1523888516, G160464177, G165179637, G1657338961, G2598085392, G3067963855, G3392305090, G3663418429, G4211410756, G4645358078, G4835671942, G4876042962, G4962106257, G5327073570, G5659690140, G6141599669, G6167497367, G6526646931, G657448715, G7452299184, G7500482128, G7900882, HYBRID QUANTUM SYSTEMS: SPINS, PHOTONS AND SUPERCONDUCTING QUBITS, G867139975, EFRI ACQUIRE: Integrated Nanophotonic Solid State Memories for Telecom Wavelength Quantum Repeaters, QII-TAQS: Quantum Metrological Platform for Single-Molecule Bio-Sensing
OpenAlex ID: W2935313550