Bulletin of the American Physical Society
APS March Meeting 2023
Volume 68, Number 3
Las Vegas, Nevada (March 5-10)
Virtual (March 20-22); Time Zone: Pacific Time
Session AA08: V: Quantum Error Correction and EntanglementFocus
|
Hide Abstracts |
Sponsoring Units: DQI Chair: Nathan McMahon, Friedrich-Alexander University Erlangen-Nurnberg Room: Virtual Room 8 |
Monday, March 20, 2023 5:00AM - 5:36AM |
AA08.00001: Quantum error correction, quantum advantage and magic measures with the Gottesman-Kitaev-Preskill code Invited Speaker: Giulia Ferrini Since when it was introduced in 2001, the Gottesman-Kitaev-Preskill (GKP) code [1] has attracted considerable attention, due to its capability of making bosonic quantum computation fault-tolerant. In this talk, I will review several results around GKP codes. First, I will argue that the performance of GKP codes for quantum error correction is hindered when dephasing noise, or finite detection efficiencies in the state recovery procedure, are present, while other bosonic codes such as binomial codes are less affected by these effects [2]. Then, using the stabiliser formalism I will show that the ingredients composing GKP quantum error correction circuits (excluding the data qubit), i.e. stabiliser GKP states together with Gaussian operations and quadrature measurements, are classically efficiently simulatable [3]. Combined with the result that GKP error-correction of the vacuum yields magic states [4] this allows us to conclude that vacuum provides quantum advantage in restricted quantum computing architectures made of stabiliser GKP states together with Gaussian operations and quadrature measurements. Finally, I will show that using the GKP encoding allows for defining a magic measure for qubits, easier to compute than other measures. |
Monday, March 20, 2023 5:36AM - 5:48AM |
AA08.00002: Beating the break-even point by repetitive quantum error correction on a photonic qubit Yuan Xu, Zhongchu Ni, Sai Li, Xiaowei Deng, Yanyan Cai, Libo Zhang, Weiting Wang, Zhen-Biao Yang, Haifeng Yu, Fei Yan, Song Liu, Chang-Ling Zou, Luyan Sun, Shi-Biao Zheng, Dapeng Yu Quantum error correction (QEC) aims for protecting logic qubits from noises by feedback control. To benefit from QEC, a redundantly encoded logic qubit needs to have a lifetime otherwise unavailable--surpass the "break-even" point. Most QEC codes work by repetitively performing feedback-control cycles, where an error, once occurs, is corrected in real time. Such repetitive QEC demonstrations have been reported on various platforms, but where the break-even point remains to be reached yet. Here we demonstrate a QEC procedure with a logic qubit binomially-encoded in a microwave cavity, dispersively coupled to an ancilla superconducting qubit. By applying a pulse featuring an ingeniously tailored frequency comb to the ancilla, we extract the error syndrome robustly and perform repetitive QEC, thereby exceeding the break-even point by 20%. |
Monday, March 20, 2023 5:48AM - 6:00AM |
AA08.00003: Qubit-oscillator concatenated codes: decoding formalism & code comparison Yijia Xu, Yixu Wang, En-Jui Kuo, Victor V Albert Concatenating bosonic error-correcting codes with qubit codes can substantially boost the error-correcting power of the original qubit codes. It is not clear how to concatenate optimally, given there are several bosonic codes and concatenation schemes to choose from, including the recently discovered GKP-stabilizer codes [arXiv:1903.12615] that allow protection of a logical bosonic mode from fluctuations of the mode's conjugate variables. We develop efficient maximum-likelihood decoders for and analyze the performance of three different concatenations of codes taken from the following set: qubit stabilizer codes, analog/Gaussian stabilizer codes, GKP codes, and GKP-stabilizer codes. We benchmark decoder performance against additive Gaussian white noise, corroborating our numerics with analytical calculations. We observe that the concatenation involving GKP-stabilizer codes outperforms the more conventional concatenation of a qubit stabilizer code with a GKP code in some cases. We also propose a GKP-stabilizer code that suppresses fluctuations in both conjugate variables without squeezing resources, and formulate qudit versions of GKP-stabilizer codes. |
Monday, March 20, 2023 6:00AM - 6:12AM |
AA08.00004: Protecting Entanglement via Quantum Error Correction Weizhou Cai, Xianghao Mu, Weiting Wang, Jie Zhou, Yuwei Ma, Xiaoxuan Pan, Ziyue Hua, Xinyu Liu, Guangming Xue, Haifeng Yu, Chang-Ling Zou, Luyan Sun Entanglement lies at the heart of quantum information science because it represents the most essential resource for quantum communication, quantum computing, quantum sensing, etc. However, this correlation between separated subsystems is fragile due to the decoherence of each subsystem, which creates the obstacle to entanglement-assisted or entanglement-enhanced quantum information processing in practice. Therefore, protecting entanglement is essential for future quantum applications. In this talk, we will introduce our recent experimental efforts on the protection of entanglement via quantum error correction (QEC). We first demonstrate the entanglement protection between two logical qubits based on separated bosonic modes by repetitively implementing QEC on each logical qubit. Then, inspired by previous experiments of entanglement purification, we also purify the entanglement through error detecting and post-selecting trajectories of logical qubits with no error. Thus, better entanglement of logical qubits has been realized by such error detection and post-selection. |
Monday, March 20, 2023 6:12AM - 6:24AM |
AA08.00005: Deterministic generation of qudit photonic graph states from quantum emitters Zahra Raissi, Sophia Economou, Edwin Barnes We propose and analyze deterministic protocols to generate qudit photonic graph states from quantum emitters. We exemplify our approach by constructing protocols to generate absolutely maximally entangled states and logical states of quantum error correcting codes. Some of these protocols make use of time-delayed feedback, while others do not. These results significantly broaden the range of multi-photon entangled states that can be produced deterministically from quantum emitters. |
Monday, March 20, 2023 6:24AM - 6:36AM |
AA08.00006: Scalable surface code decoders with parallelization in time Fang Zhang Fast classical processing is essential for most quantum fault-tolerance architectures. We introduce a sliding-window decoding scheme that provides fast classical processing for common topological codes through parallelism. Our scheme divides the syndromes in spacetime into overlapping windows along the time direction, which can be decoded in parallel with any inner decoder. With this parallelism, our scheme can solve the decoding throughput problem as the code scales up, even if the inner decoder is slow. When using min-weight perfect matching and union-find as the inner decoders for the surface code quantum memory, we observe circuit-level thresholds of 0.68% and 0.55%, respectively, which are almost identical to 0.70% and 0.55% for the batch decoding. |
Monday, March 20, 2023 6:36AM - 6:48AM |
AA08.00007: Autonomous Global Decoders for Quantum Memories Oles Shtanko, Yu-Jie Liu, Simon Lieu, Victor V Albert, Alexey V Gorshkov Autonomous quantum memories provide passive protection of quantum information using engineered dissipation that yields an ``always-on" decoder. We consider a simple theoretical model of universal global autonomous decoders that can be constructed from a wide family of quantum codes. We prove bounds on the logical error rate as a function of the rates of correction and noise. We find that such a model typically require correction rates that scale polynomially with system size to achieve exponential suppression of logical errors. We apply our results to existing quantum codes codes, including the five-qubit code, the toric code, and the binomial code. |
Monday, March 20, 2023 6:48AM - 7:00AM |
AA08.00008: Imaging stars with quantum error correction Zixin Huang The development of high-resolution, large-baseline optical interferometers would revolutionize astronomical imaging. However, classical techniques are hindered by physical limitations including loss, noise, and the fact that the received light is generally quantum in nature. We show how to overcome these issues using quantum communication techniques. |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700