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Related papers: Logical coherence in 2D compass codes

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We introduce tile codes, a simple yet powerful way of constructing quantum codes that are local on a planar 2D-lattice. Tile codes generalize the usual surface code by allowing for a bit more flexibility in terms of locality and stabilizer…

Cyclic codes are an important class of linear codes. Bounding the minimum distance of cyclic codes is a long-standing research topic in coding theory, and several well-known and basic results have been developed on this topic. Recently,…

Information Theory · Computer Science 2023-10-12 Jing Qiu , Weijun Fang , Fang-Wei Fu

We study the fundamental limits on the reliable storage of quantum information in lattices of qubits by deriving tradeoff bounds for approximate quantum error correcting codes. We introduce a notion of local approximate correctability and…

Quantum Physics · Physics 2021-10-26 Steven T. Flammia , Jeongwan Haah , Michael J. Kastoryano , Isaac H. Kim

We compare the effect of single qubit incoherent and coherent errors on the logical error rate of the Steane [[7,1,3]] quantum error correction code by performing an exact full-density-matrix simulation of an error correction step. We find…

Quantum Physics · Physics 2016-11-02 Mauricio Gutiérrez , Conor Smith , Livia Lulushi , Smitha Janardan , Kenneth R. Brown

Orthogonal geometric constructions are the basis of many many quantum error-correcting codes (QEC), but strict orthogonality constraints limit design flexibility and resource efficiency. We introduce a quasi-orthogonal geometric framework…

Quantum error correction becomes a practical possibility only if the physical error rate is below a threshold value that depends on a particular quantum code, syndrome measurement circuit, and decoding algorithm. Here we present an…

For any positive integer $g \ge 2$, we derive general condition for the existence of a $2g$-cycle in the Tanner graph of two-dimensional ($2$-D) classical quasi-cyclic (QC) low-density parity-check (LDPC) codes. Depending on whether $p$ is…

Information Theory · Computer Science 2026-01-21 Pavan Kumar , Shayan Srinivasa Garani

We propose a new class of error-correcting dynamic codes in two and three dimensions that has no explicit connection to any parent subsystem code. The two-dimensional code, which we call the CSS honeycomb code, is geometrically similar to…

Quantum Physics · Physics 2023-10-26 Margarita Davydova , Nathanan Tantivasadakarn , Shankar Balasubramanian

In this work we introduce two code families, which we call the heavy hexagon code and heavy square code. Both code families are implemented by assigning physical data and ancilla qubits to both vertices and edges of low degree graphs. Such…

The realization of quantum error correction is an essential ingredient for reaching the full potential of fault-tolerant universal quantum computation. Using a range of different schemes, logical qubits can be redundantly encoded in a set…

We identify a period-4 measurement schedule for the checks of the Bacon-Shor code that fully covers spacetime with constant-weight detectors, and is numerically observed to provide the code with a threshold. Unlike previous approaches, our…

Quantum Physics · Physics 2026-02-09 M. Sohaib Alam , Jun Zen , Thomas R. Scruby

We can design efficient quantum error-correcting (QEC) codes by tailoring them to our choice of quantum architecture. Useful tools for constructing such codes include Clifford deformations and appropriate gauge fixings of compass codes. In…

Quantum Physics · Physics 2026-04-22 Julie A. Campos , Kenneth R. Brown

We study how the resilience of the surface code is affected by the coupling to a non-Markovian environment at zero temperature. The qubits in the surface code experience an effective dynamics due to the coupling to the environment that…

Quantum Physics · Physics 2014-07-18 Pejman Jouzdani , Eduardo R. Mucciolo

Quantum synchronizable error-correcting codes are special quantum error-correcting codes that are designed to correct both the effect of quantum noise on qubits and misalignment in block synchronization. It is known that in principle such a…

Quantum Physics · Physics 2014-11-17 Yuichiro Fujiwara , Peter Vandendriessche

Error-correcting codes over the real field are studied which can locate outlying computational errors when performing approximate computing of real vector--matrix multiplication on resistive crossbars. Prior work has concentrated on…

Information Theory · Computer Science 2024-02-22 Hengjia Wei , Ron M. Roth

We propose a novel method to calculate logical error rates in surface codes, assuming independent and identically distributed physical errors. We show how to use our method to analyze hypothetical quantum computers with various…

Quantum Physics · Physics 2026-05-06 Shaked Regev , Daniel Dilley , Andrea Delgado , Ryan Bennink

Demonstrating subthreshold scaling of a surface-code quantum memory on hardware whose native connectivity does not match the code remains a central challenge. We address this on IBM heavy-hex superconducting processors by co-designing the…

Quantum Physics · Physics 2025-10-22 Arian Vezvaee , Cesar Benito , Mario Morford-Oberst , Alejandro Bermudez , Daniel A. Lidar

Realizing the full potential of quantum computation requires quantum error correction (QEC), with most recent breakthrough demonstrations of QEC using the surface code. QEC codes use multiple noisy physical qubits to encode information in…

We formally define homological quantum rotor codes which use multiple quantum rotors to encode logical information. These codes generalize homological or CSS quantum codes for qubits or qudits, as well as linear oscillator codes which…

Quantum Physics · Physics 2024-12-02 Christophe Vuillot , Alessandro Ciani , Barbara M. Terhal

Topological quantum codes are intrinsically fault-tolerant to local noise, and underlie the theory of topological phases of matter. We explore geometry to enhance the performance of topological quantum codes by rotating the four dimensional…