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Dr Vivien Kendon's Outputs (25)

Generalizing multipartite concentratable entanglement for practical applications: mixed, qudit and optical states (2024)
Journal Article
Foulds, S., Prove, O., & Kendon, V. (2024). Generalizing multipartite concentratable entanglement for practical applications: mixed, qudit and optical states. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 382(2287), Article 20240411. https://doi.org/10.1098/rsta.2024.0411

The controlled SWAP test for detecting and quantifying entanglement applied to pure qubit states is robust to small errors in the states and efficient for large multi-qubit states (Foulds et al. 2021 Quantum Sci. Technol. 6, 035002 (doi:10.1088/2058-... Read More about Generalizing multipartite concentratable entanglement for practical applications: mixed, qudit and optical states.

Quantum algorithms for scientific computing. (2024)
Journal Article
Au-Yeung, R., Camino, B., Rathore, O., & Kendon, V. (2024). Quantum algorithms for scientific computing. Reports on Progress in Physics, 87(11), Article 116001. https://doi.org/10.1088/1361-6633/ad85f0

Quantum computing promises to provide the next step up in computational power for diverse application areas. In this review, we examine the science behind the quantum hype, and the breakthroughs required to achieve true quantum advantage in real worl... Read More about Quantum algorithms for scientific computing..

Cycle discrete-time quantum walks on a noisy quantum computer (2024)
Journal Article
Wadhia, V., Chancellor, N., & Kendon, V. (2024). Cycle discrete-time quantum walks on a noisy quantum computer. The European Physical Journal D, 78(3), Article 29. https://doi.org/10.1140/epjd/s10053-023-00795-2

The rapid development of quantum computing has led to increasing interest in quantum algorithms for a variety of different applications. Quantum walks have also experienced a surge in interest due to their potential use in quantum algorithms. Using t... Read More about Cycle discrete-time quantum walks on a noisy quantum computer.

Using copies can improve precision in continuous-time quantum computing (2023)
Journal Article
Bennett, J., Callison, A., O’Leary, T., West, M., Chancellor, N., & Kendon, V. (2023). Using copies can improve precision in continuous-time quantum computing. Quantum Science and Technology, 8(3), Article 035031. https://doi.org/10.1088/2058-9565/acdcb5

In the quantum optimisation setting, we build on a scheme introduced by Young et al (2013 Phys. Rev. A 88 062314), where physical qubits in multiple copies of a problem encoded into an Ising spin Hamiltonian are linked together to increase the logica... Read More about Using copies can improve precision in continuous-time quantum computing.

Comparing the hardness of MAX 2-SAT problem instances for quantum and classical algorithms (2023)
Journal Article
Mirkarimi, P., Callison, A., Light, L., Chancellor, N., & Kendon, V. (2023). Comparing the hardness of MAX 2-SAT problem instances for quantum and classical algorithms. Physical Review Research, 5(2), https://doi.org/10.1103/physrevresearch.5.023151

An algorithm for a particular problem may find some instances of the problem easier and others harder to solve, even for a fixed input size. We numerically analyze the relative hardness of MAX 2-SAT problem instances for various continuous-time quant... Read More about Comparing the hardness of MAX 2-SAT problem instances for quantum and classical algorithms.

Experimental test of search range in quantum annealing (2021)
Journal Article
Chancellor, N., & Kendon, V. (2021). Experimental test of search range in quantum annealing. Physical Review A, 104(1), Article 012604. https://doi.org/10.1103/physreva.104.012604

We construct an Ising Hamiltonian with an engineered energy landscape such that it has a local energy minimum which is near the true global minimum solution and further away from a false minimum. Using a technique established in previous experiments,... Read More about Experimental test of search range in quantum annealing.

The controlled SWAP test for determining quantum entanglement (2021)
Journal Article
Foulds, S., Kendon, V., & Spiller, T. (2021). The controlled SWAP test for determining quantum entanglement. Quantum Science and Technology, 6(3), Article 035002. https://doi.org/10.1088/2058-9565/abe458

Quantum entanglement is essential to the development of quantum computation, communications, and technology. The controlled SWAP test, widely used for state comparison, can be adapted to an efficient and useful test for entanglement of a pure state.... Read More about The controlled SWAP test for determining quantum entanglement.

Energetic Perspective on Rapid Quenches in Quantum Annealing (2021)
Journal Article
Callison, A., Festenstein, M., Chen, J., Nita, L., Kendon, V., & Chancellor, N. (2021). Energetic Perspective on Rapid Quenches in Quantum Annealing. PRX Quantum, 2(1), Article 010338. https://doi.org/10.1103/prxquantum.2.010338

There are well-developed theoretical tools to analyze how quantum dynamics can solve computational problems by varying Hamiltonian parameters slowly, near the adiabatic limit. On the other hand, there are relatively few tools to understand the opposi... Read More about Energetic Perspective on Rapid Quenches in Quantum Annealing.

The representational entity in physical computing (2020)
Journal Article
Stepney, S., & Kendon, V. (2021). The representational entity in physical computing. Natural Computing, 20(2), 233-242. https://doi.org/10.1007/s11047-020-09805-3

We have developed abstraction/representation (AR) theory to answer the question “When does a physical system compute?” AR theory requires the existence of a representational entity (RE), but the vanilla theory does not explicitly include the RE in it... Read More about The representational entity in physical computing.

Finding spin glass ground states using quantum walks (2019)
Journal Article
Callison, A., Chancellor, N., Mintert, F., & Kendon, V. (2019). Finding spin glass ground states using quantum walks. New Journal of Physics, 21, Article 123022. https://doi.org/10.1088/1367-2630/ab5ca2

Quantum computation using continuous-time evolution under a natural hardware Hamiltonian is a promising near- and mid-term direction toward powerful quantum computing hardware. We investigate the performance of continuous-time quantum walks as a tool... Read More about Finding spin glass ground states using quantum walks.

Practical designs for permutation-symmetric problem Hamiltonians on hypercubes (2019)
Journal Article
Dodds, A. B., Kendon, V., Adams, C. S., & Chancellor, N. (2019). Practical designs for permutation-symmetric problem Hamiltonians on hypercubes. Physical Review A, 100(3), Article 032320. https://doi.org/10.1103/physreva.100.032320

We present a method to experimentally realize large-scale permutation-symmetric Hamiltonians for continuous-time quantum protocols such as quantum walks and adiabatic quantum computation. In particular, the method can be used to perform an encoded co... Read More about Practical designs for permutation-symmetric problem Hamiltonians on hypercubes.

Quantum search with hybrid adiabatic–quantum-walk algorithms and realistic noise (2019)
Journal Article
Morley, J. G., Chancellor, N., Bose, S., & Kendon, V. (2019). Quantum search with hybrid adiabatic–quantum-walk algorithms and realistic noise. Physical Review A, 99(2), Article 022339. https://doi.org/10.1103/physreva.99.022339

Computing using a continuous-time evolution, based on the natural interaction Hamiltonian of the quantum computer hardware, is a promising route to building useful quantum computers in the near term. Adiabatic quantum computing, quantum annealing, co... Read More about Quantum search with hybrid adiabatic–quantum-walk algorithms and realistic noise.

Protecting quantum memories using coherent parity check codes (2018)
Journal Article
Roffe, J., Headley, D., Chancellor, N., Horsman, D., & Kendon, V. (2018). Protecting quantum memories using coherent parity check codes. Quantum Science and Technology, 3(3), Article 035010. https://doi.org/10.1088/2058-9565/aac64e

Coherent parity check (CPC) codes are a new framework for the construction of quantum error correction codes that encode multiple qubits per logical block. CPC codes have a canonical structure involving successive rounds of bit and phase parity check... Read More about Protecting quantum memories using coherent parity check codes.

The quantum walk search algorithm: factors affecting efficiency (2018)
Journal Article
Lovett, N. B., Everitt, M., Heath, R. M., & Kendon, V. (2019). The quantum walk search algorithm: factors affecting efficiency. Mathematical Structures in Computer Science, 29(3), 389-429. https://doi.org/10.1017/s0960129518000051

We carry out a numerical study of the quantum walk search algorithm of Shenvi, Kempe and Whaley Shenvi et al. (2003) and the factors that affect its efficiency in finding an individual state from an unsorted set. Previous work has focused purely on t... Read More about The quantum walk search algorithm: factors affecting efficiency.

Ancilla-driven quantum computation for qudits and continuous variables (2017)
Journal Article
Proctor, T., Giulian, M., Korolkova, N., Andersson, E., & Kendon, V. (2017). Ancilla-driven quantum computation for qudits and continuous variables. Physical Review A, 95(5), Article 052317. https://doi.org/10.1103/physreva.95.052317

Although qubits are the leading candidate for the basic elements in a quantum computer, there are also a range of reasons to consider using higher-dimensional qudits or quantum continuous variables (QCVs). In this paper, we use a general “quantum var... Read More about Ancilla-driven quantum computation for qudits and continuous variables.

Quantum walk transport properties on graphene structures (2016)
Journal Article
Bougroura, H., Aissaoui, H., Chancellor, N., & Kendon, V. (2016). Quantum walk transport properties on graphene structures. Physical Review A, 94(6), Article 062331. https://doi.org/10.1103/physreva.94.062331

We present numerical studies of quantum walks on C 60 and related graphene structures to investigate their transport properties. Also known as a honeycomb lattice, the lattice formed by carbon atoms in the graphene phase can be rolled up to form nano... Read More about Quantum walk transport properties on graphene structures.

Hybrid quantum computing with ancillas (2016)
Journal Article
Proctor, T. J., & Kendon, V. (2016). Hybrid quantum computing with ancillas. Contemporary Physics, 57(4), 459-476. https://doi.org/10.1080/00107514.2016.1152700

In the quest to build a practical quantum computer, it is important to use efficient schemes for enacting the elementary quantum operations from which quantum computer programs are constructed. The opposing requirements of well-protected quantum data... Read More about Hybrid quantum computing with ancillas.

Heterotic computing: exploiting hybrid computational devices (2015)
Journal Article
Kendon, V., Sebald, A., & Stepney, S. (2015). Heterotic computing: exploiting hybrid computational devices. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 373(2046), Article 20150091. https://doi.org/10.1098/rsta.2015.0091

Current computational theory deals almost exclusively with single models: classical, neural, analogue, quantum, etc. In practice, researchers use ad hoc combinations, realizing only recently that they can be fundamentally more powerful than the indiv... Read More about Heterotic computing: exploiting hybrid computational devices.