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Related papers: Universal Quantum Computation and Leakage Reductio…

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To unleash the potential of quantum computers, noise effects on qubits' performance must be carefully managed. The decoders responsible for diagnosing noise-induced computational errors must use resources efficiently to enable scaling to…

Superconducting qubits are a promising platform for building fault-tolerant quantum computers, with recent achievement showing the suppression of logical error with increasing code size. However, leakage into non-computational states, a…

In this paper, we propose an efficient compilation method for distributed quantum computing (DQC) using the Linear Nearest Neighbor (LNN) architecture. By exploiting the LNN topology's symmetry, we optimize quantum circuit compilation for…

Quantum simulators are essential tools for developing and testing quantum algorithms. However, the high-frequency traversal characteristic of quantum simulators represents an unprecedented demand in the history of IT, and existing…

Emerging Technologies · Computer Science 2025-08-22 Mingyang Yu , Haorui Yang , Donglin Wang , Desheng Kong , Ji Du , Yulong Fu , Wei Wang , Jing Xu

We design efficient controlled-rotation gates with arbitrary angle acting on three-spin encoded qubits for exchange-only quantum computation. Two pulse sequence constructions are given. The first is motivated by an analytic derivation of…

Quantum Physics · Physics 2020-09-28 Daniel Zeuch , N. E. Bonesteel

In this work, inspired by the study of semidefinite programming for block-diagonalizing matrix *-algebras, we propose an algorithm that can find the algebraic structure of decoherence-free subspaces (DFS's) for a given noisy quantum…

Quantum Physics · Physics 2013-02-19 Xiaoting Wang , Mark Byrd , Kurt Jacobs

In order to demonstrate non-trivial quantum computations experimentally, such as the synthesis of arbitrary entangled states, it will be useful to understand how to decompose a desired quantum computation into the shortest possible sequence…

Quantum Physics · Physics 2009-11-10 Farrokh Vatan , Colin Williams

We present a scheme for correcting for crosstalk- and noise-induced errors in exchange-coupled singlet-triplet semiconductor double quantum dot qubits. While exchange coupling allows the coupling strength to be controlled independently of…

Mesoscale and Nanoscale Physics · Physics 2018-07-05 Donovan Buterakos , Robert E. Throckmorton , S. Das Sarma

Quantum codes excel at correcting local noise but fail to correct leakage faults that excite qubits to states outside the computational space. Aliferis and Terhal have shown that an accuracy threshold exists for leakage faults using gadgets…

Quantum Physics · Physics 2015-09-29 Martin Suchara , Andrew W. Cross , Jay M. Gambetta

The \textit{heavy-fluxonium} circuit is a promising building block for superconducting quantum processors due to its long relaxation and dephasing time at the half-flux frustration point. However, the suppressed charge matrix elements and…

We introduce protocols for designing and manipulating qubits with ultracold alkali atoms in 3D optical lattices. These qubits are formed from two-atom spin superposition states that create a decoherence-free subspace immune to stray…

Quantum Physics · Physics 2023-05-23 Mikhail Mamaev , Joseph H. Thywissen , Ana Maria Rey

A single physical interaction might not be universal for quantum computation in general. It has been shown, however, that in some cases it can generate universal quantum computation over a subspace. For example, by encoding logical qubits…

Quantum Physics · Physics 2007-05-23 M. Hsieh , J. Kempe , S. Myrgren , K. B. Whaley

A new scheme of quantum key distribution (QKD) using frequency and time coding is proposed, in which the security is based on the frequency-time uncertainty relation. In this scheme, the binary information sequence is encoded randomly on…

Quantum Physics · Physics 2015-05-18 Chang-hua Zhu , Chang-xing Pei , Dong-xiao Quan , Nan Chen , Yun-hui Yi

Quantum computers require high fidelity quantum gates. These gates are obtained by routine calibration tasks that eat into the availability of cloud-based devices. Restless circuit execution speeds-up characterization and calibration by…

Quantum Physics · Physics 2023-11-10 Conrad J. Haupt , Daniel J. Egger

Decoherence-induced leakage errors can potentially damage physical or logical qubits by coupling them to other system levels. Here we report the first experimental implementation of Leakage Elimination Operators (LEOs) that aims to reduce…

Quantum Physics · Physics 2020-07-10 Beatriz Garcia Markaida , Lian-Ao Wu

Fewer-qubit quantum logic gate, serving as a basic unit for constructing universal multiqubit gates, has been widely applied in quantum computing and quantum information. However, traditional constructions for fewer-qubit gates often…

Quantum Physics · Physics 2021-12-20 Rui Li , Shurui Li , Dongmin Yu , Jing Qian , Weiping Zhang

We implement dynamical decoupling techniques to mitigate noise and enhance the lifetime of an entangled state that is formed in a superconducting flux qubit coupled to a microscopic two-level system. By rapidly changing the qubit's…

Quantitative information flow (QIF) is traditionally defined as the expected value of information leakage over all feasible program runs and it fails to identify vulnerable programs where only limited number of runs leak large amount of…

Cryptography and Security · Computer Science 2019-05-14 Bao Trung Chu , Kenji Hashimoto , Hiroyuki Seki

To avoid prohibitive overheads in performing fault-tolerant quantum computation, the decoding problem needs to be solved accurately and at speeds sufficient for fast feedback. Existing decoding systems fail to satisfy both of these…

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