English
Related papers

Related papers: Time-optimal quantum computation

200 papers

Code-switching offers a route to universal, fault-tolerant quantum computation by circumventing the limitation implied by the Eastin-Knill theorem against a universal transversal gate set within a single quantum code. Here, we present a…

Quantum Physics · Physics 2026-04-07 Shixin Wu , Dawei Zhong , Todd A. Brun , Daniel A. Lidar

We consider quantum circuits composed of Clifford and T gates. In this context the T gate has a special status since it confers universal computation when added to the (classically simulable) Clifford gates. However it can be very expensive…

Quantum Physics · Physics 2013-08-21 David Gosset , Vadym Kliuchnikov , Michele Mosca , Vincent Russo

Fault-tolerant quantum computers rely on Quantum Error-Correcting Codes (QECCs) to protect information from noise. However, no single error-correcting code supports a fully transversal and therefore fault-tolerant implementation of all…

Quantum Physics · Physics 2025-12-05 Erik Weilandt , Tom Peham , Robert Wille

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…

The Gottesman-Knill theorem asserts that a quantum circuit composed of Clifford gates can be efficiently simulated on a classical computer. Here we revisit this theorem and extend it to quantum circuits composed of Clifford and T gates,…

Quantum Physics · Physics 2019-04-11 Sergey Bravyi , David Gosset

Fault-tolerant quantum computation (FTQC) is essential to implement quantum algorithms in a noise-resilient way, and thus to enjoy advantages of quantum computers even with presence of noise. In FTQC, a quantum circuit is decomposed into…

Quantum Physics · Physics 2025-07-23 Kohdai Kuroiwa , Yuya O. Nakagawa

We present two classical algorithms for the simulation of universal quantum circuits on $n$ qubits constructed from $c$ instances of Clifford gates and $t$ arbitrary-angle $Z$-rotation gates such as $T$ gates. Our algorithms complement each…

Quantum Physics · Physics 2022-06-27 Hakop Pashayan , Oliver Reardon-Smith , Kamil Korzekwa , Stephen D. Bartlett

Magic states are a foundational resource for universal quantum computation. To survive in a realistic noisy environment, magic states must be prepared fault-tolerantly and protected by a quantum error-correcting code. The recent discovery…

Quantum Physics · Physics 2026-02-02 Dominic J. Williamson

Quantum computing relies on quantum error correction for high-fidelity logical operations, but scaling to achieve near-term quantum utility is highly resource-intensive. High-rate quantum LDPC codes can reduce error correction overhead, yet…

Quantum Physics · Physics 2025-11-11 Laura Pecorari , Francesco Paolo Guerci , Hugo Perrin , Guido Pupillo

Several classes of quantum circuits have been shown to provide a quantum computational advantage under certain assumptions. The study of ever more restricted classes of quantum circuits capable of quantum advantage is motivated by possible…

Quantum Physics · Physics 2024-04-10 Michael de Oliveira , Luís S. Barbosa , Ernesto F. Galvão

Conventional quantum error correcting codes require multiple rounds of measurements to detect errors with enough confidence in fault-tolerant scenarios. Here I show that for suitable topological codes a single round of local measurements is…

Quantum Physics · Physics 2016-05-13 H. Bombin

This paper proves the threshold result, which asserts that quantum computation can be made robust against errors and inaccuracies, when the error rate, $\eta$, is smaller than a constant threshold, $\eta_c$. The result holds for a very…

Quantum Physics · Physics 2007-05-23 Dorit Aharonov , Michael Ben-Or

We study the use of triorthogonal codes for universal fault-tolerant quantum computation and propose two methods to circumvent the Eastin-Knill theorem, which prohibits any single quantum error-correcting code from supporting both…

Quantum Physics · Physics 2025-11-06 Dawei Jiao , Mahdi Bayanifar , Alexei Ashikhmin , Olav Tirkkonen

Fault-tolerant quantum computing typically requires the transpilation of arbitrary quantum circuits into a finite, universal gate set, such as Clifford+T. As a baseline, Diagonal approximation can be used for synthesizing single-qubit Pauli…

Quantum Physics · Physics 2026-05-12 Gilad Kishony , Avi Elazari , Ron Cohen , Lior Gazit

Reliable qubits are difficult to engineer, but standard fault-tolerance schemes use seven or more physical qubits to encode each logical qubit, with still more qubits required for error correction. The large overhead makes it hard to…

Quantum Physics · Physics 2018-11-02 Rui Chao , Ben W. Reichardt

Quantum states are very delicate, so it is likely some sort of quantum error correction will be necessary to build reliable quantum computers. The theory of quantum error-correcting codes has some close ties to and some striking differences…

Quantum Physics · Physics 2009-04-17 Daniel Gottesman

Clifford gates play a role in the optimisation of Clifford+T circuits. Reducing the count and the depth of Clifford gates, as well as the optimal scheduling of T gates, influence the hardware and the time costs of executing quantum…

Quantum Physics · Physics 2019-06-18 Alexandru Paler , Robert Basmadjian

The discovery of quantum error correction has greatly improved the long-term prospects for quantum computing technology. Encoded quantum information can be protected from errors that arise due to uncontrolled interactions with the…

Quantum Physics · Physics 2007-05-23 John Preskill

Quantum code surgery is a promising technique to perform fault-tolerant computation on quantum low-density parity-check codes. Recent developments have significantly reduced the space overhead of surgery. However, generic surgery operations…

Quantum Physics · Physics 2025-10-17 Alexander Cowtan , Zhiyang He , Dominic J. Williamson , Theodore J. Yoder

Medium-scale quantum devices that integrate about hundreds of physical qubits are likely to be developed in the near future. However, such devices will lack the resources for realizing quantum fault tolerance. Therefore, the main challenge…

Quantum Physics · Physics 2021-12-24 Chao Song , Jing Cui , H. Wang , J. Hao , H. Feng , Ying Li