297 citations · 1.4k across the 44 of their papers we have counts for
44 papers
Cycle discrete-time quantum walks on a noisy quantum computer
Vivek Wadhia, Nicholas Chancellor, Viv Kendon
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…
A thermodynamic approach to optimization in complex quantum systems
Alberto Imparato, Nicholas Chancellor, Gabriele De Chiara
We consider the problem of finding the energy minimum of a complex quantum Hamiltonian by employing a non-Markovian bath prepared in a low energy state. The energy minimization pro…
NP-hard but no longer hard to solve? Using quantum computing to tackle optimization problems
Rhonda Au-Yeung, Nicholas Chancellor, Pascal Halffmann
In the last decade, public and industrial research funding has moved quantum computing from the early promises of Shor's algorithm through experiments to the era of noisy intermedi…
Suppressing unwanted fluctuations in QAOA and approximate quantum annealing
Touheed Anwar Atif, Catherine Potts, David Haycraft +2
The quantum approximate optimisation algorithm (QAOA) was partially inspired by digitising quantum annealing. Based on this inspiration, we develop techniques to use the additional…
Hybrid quantum-classical algorithms in the noisy intermediate-scale quantum era and beyond
Adam Callison, Nicholas Chancellor
Hybrid quantum-classical algorithms are central to much of the current research in quantum computing, particularly when considering the noisy intermediate-scale quantum (NISQ) era,…
Comparing the hardness of MAX 2-SAT problem instances for quantum and classical algorithms
Puya Mirkarimi, Adam Callison, Lewis Light +2
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 analyse the relative har…
Using copies to improve precision in continuous-time quantum computing
Jemma Bennett, Adam Callison, Tom O'Leary +3
In the quantum optimisation setting, we build on a scheme introduced by Young et al [PRA 88, 062314, 2013], where physical qubits in multiple copies of a problem encoded into an Is…
Controller-based Energy-Aware Wireless Sensor Network Routing using Quantum Algorithms
Jie Chen, Prasanna Date, Nicholas Chancellor +2
Energy efficient routing in wireless sensor networks has attracted attention from researchers in both academia and industry, most recently motivated by the opportunity to use SDN (…
Understanding domain-wall encoding theoretically and experimentally
Jesse Berwald, Nicholas Chancellor, Raouf Dridi
We analyze the method of encoding pairwise interactions of higher-than-binary discrete variables (these models are sometimes referred to as discrete quadratic models) into binary v…
Inclusive learning for quantum computing: supporting the aims of quantum literacy using the puzzle game Quantum Odyssey
Laurentiu Nita, Nicholas Chancellor, Laura Mazzoli Smith +2
With a vast domain of applications and now having quantum computing hardware available for commercial use, an education challenge arises in getting people of various background to…
Performance of Domain-Wall Encoding for Quantum Annealing
Jie Chen, Tobias Stollenwerk, Nicholas Chancellor
In this paper we experimentally test the performance of the recently proposed domain-wall encoding of discrete variables from [Chancellor Quantum Sci. Technol. 4 045004] on Ising m…
AKLT-states as ZX-diagrams: diagrammatic reasoning for quantum states
Richard D. P. East, John van de Wetering, Nicholas Chancellor +1
From Feynman diagrams to tensor networks, diagrammatic representations of computations in quantum mechanics have catalysed progress in physics. These diagrams represent the underly…
Fluctuation guided search in quantum annealing
Nicholas Chancellor
Quantum annealing has great promise in leveraging quantum mechanics to solve combinatorial optimisation problems. However, to realize this promise to it's fullest extent we must ap…
Search range in experimental quantum annealing
Nicholas Chancellor, Viv Kendon
We construct an Ising Hamiltonian with an engineered energy landscape such that it has a local energy minimum which is near to the true global minimum solution, and further away fr…
An energetic perspective on rapid quenches in quantum annealing
Adam Callison, Max Festenstein, Jie Chen +3
There are well developed theoretical tools to analyse how quantum dynamics can solve computational problems by varying Hamiltonian parameters slowly, near the adiabatic limit. On t…
Toward a standardized methodology for constructing quantum computing use cases
Nicholas Chancellor, Robert Cumming, Tim Thomas
We propose a standardized methodology for developing and evaluating use cases for quantum computers and quantum inspired methods. This methodology consists of a standardized set of…
Error measurements for a quantum annealer using the one-dimensional Ising model with twisted boundaries
Nicholas Chancellor, Philip J. D. Crowley, Tanja Đurić +5
A finite length ferromagnetic chain with opposite spin polarisation imposed at its two ends is one of the simplest frustrated spin models. In the clean classical limit the domain w…
The challenge and opportunities of quantum literacy for future education and transdisciplinary problem-solving
Laurentiu Nita, Laura Mazzoli Smith, Nicholas Chancellor +1
Resulting from cross-disciplinary dialogue between physicists, computer scientists, educationalists, and industrial end users, we propose the concept of quantum literacy as one mea…
Quantum Computing for Quantum Tunnelling
Steven Abel, Nicholas Chancellor, Michael Spannowsky
We demonstrate how quantum field theory problems can be embedded on quantum annealers. The general method we use is a discretisation of the field theory problem into a general Isin…
Decoding quantum error correction with Ising model hardware
Joschka Roffe, Stefan Zohren, Dominic Horsman +1
Fault tolerant quantum computers will require efficient co-processors for real-time decoding of their adopted quantum error correction protocols. In this work we examine the possib…
Domain wall encoding of discrete variables for quantum annealing and QAOA
Nicholas Chancellor
In this paper I propose a new method of encoding discrete variables into Ising model qubits for quantum optimization. The new method is based on the physics of domain walls in one…
Finding spin-glass ground states using quantum walks
Adam Callison, Nicholas Chancellor, Florian Mintert +1
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…
Embedding quadratization gadgets on Chimera and Pegasus graphs
Nike Dattani, Nick Chancellor
We group all known quadratizations of cubic and quartic terms in binary optimization problems into six and seven unique graphs respectively. We then perform a minor embedding of th…
Pegasus: The second connectivity graph for large-scale quantum annealing hardware
Nike Dattani, Szilard Szalay, Nick Chancellor
Pegasus is a graph which offers substantially increased connectivity between the qubits of quantum annealing hardware compared to the graph Chimera. It is the first fundamental cha…