Journal publications

2024

Squeezing, trisqueezing, and quadsqueezing in a spin-oscillator system

O. Băzăvan, S. Saner, D. J. Webb, E. M. Ainley, P. Drmota, D. P. Nadlinger, G. Araneda, D. M. Lucas, C. J. Ballance, R. Srinivas
(Preprint)

Robust and fast microwave-driven quantum logic for trapped-ion qubits

M. A. Weber, M. F. Gely, R. K. Hanley, T. P. Harty, A. D. Leu, C. M. Löschnauer, D. P. Nadlinger, D. M. Lucas
(Preprint)

 

2023

Focusing of quantum gate interactions using dynamical decoupling

M. C. Smith, A. D. Leu, M. F. Gely, D. M. Lucas     
(Preprint)

Synthetic Z2 gauge theories based on parametric excitations of trapped ions

O. Băzăvan, S. Saner, E. Tirrito, G. Araneda, R. Srinivas, A. Bermudez 
(Preprint)

Mode mixing and losses in misaligned microcavities

W. J. Hughes, T. H. Doherty, J. A. Blackmore, P. Horak, J. F. Goodwin     
Opt. Express 31, 32619-32636 (2023)     
(Article, Preprint)

Efficient operator method for modelling mode mixing in misaligned optical cavities

W. J. Hughes, T. H. Doherty, J. A. Blackmore, P. Horak, J. F. Goodwin
Phys. Rev. A 109, 013524    
(Article, Preprint)

Improving trapped-ion-qubit memories via code-mediated error-channel balancing

Y. Seis, B. J. Brown, A. S. Sørensen, J. F. Goodwin     
Phys. Rev. A 107, 052417 (2023)     
(Article, Preprint)

Fast, high-fidelity addressed single-qubit gates using efficient composite pulse sequences

A. D. Leu, M. F. Gely, M. A. Weber, M. C. Smith, D. P. Nadlinger, D. M. Lucas     
Phys. Rev. Lett. 131, 120601 (2023)
(Article, Preprint)

Breaking the entangling gate speed limit for trapped-ion qubits using a phase-stable standing wave

S. Saner, O. Băzăvan, M. Minder, P. Drmota, D. J. Webb, G. Araneda, R. Srinivas, D. M. Lucas, C. J. Ballance     
Phys. Rev. Lett. 131, 220601 (2023)
(Article, Preprint)

Verifiable blind quantum computing with trapped ions and single photons

P. Drmota, D. P. Nadlinger, D. Main, B. C. Nichol, E. M. Ainley, D. Leichtle, A. Mantri, E. Kashefi, R. Srinivas, G. Araneda, C. J. Ballance, D. M. Lucas     
(Preprint)

Generative modeling with quantum neurons

K. Gili, R. S. Kumar, M. Sveistrys, C. J. Ballance     
(Preprint)

 

2022

Robust quantum memory in a trapped-ion quantum network node

P. Drmota, D. Main, D. P. Nadlinger, B. C. Nichol, M. A. Weber, E. M. Ainley, A. Agrawal, R. Srinivas, G. Araneda, C. J. Ballance, D. M. Lucas 
Phys. Rev. Lett. 130, 090803 (2023)
(Article, Preprint)

Synthesizing a \(\bf{\hat{\sigma}_z}\) spin-dependent force for optical, metastable, and ground state trapped-ion qubits

O. Bǎzǎvan, S. Saner, M. Minder, A. C. Hughes, R. T. Sutherland, D. M. Lucas, R. Srinivas, C. J. Ballance     
Phys. Rev. A 107, 022617
(Article, Preprint)

Cryogenic ion trap system for high-fidelity near-field microwave-driven quantum logic

M. A. Weber, C. Löschnauer, J. Wolf, M. F. Gely, R. K. Hanley, J. F. Goodwin, C. J. Ballance, T. P. Harty, D. M. Lucas
Quantum Sci. Technol. 9 015007 (2023)
(Article, Preprint)

 

2021

Optimisation of scalable ion-cavity interfaces for quantum photonic networks

S. Gao, J. A. Blackmore, W. J. Hughes, T. H. Doherty, J. F. Goodwin     
Phys. Rev. Applied 19, 014033 (2022)     
(Article, Preprint)

An elementary quantum network of entangled optical atomic clocks

B. C. Nichol, R. Srinivas, D. P. Nadlinger, P. Drmota, D. Main, G. Araneda, C. J. Ballance, D. M. Lucas     
Nature 609, 689–694 (2022)     
(Article, Preprint)

Experimental quantum key distribution certified by Bell's theorem

D. P. Nadlinger, P. Drmota, B. C. Nichol, G. Araneda, D. Main, R. Srinivas, D. M. Lucas, C. J. Ballance, K. Ivanov, E. Y-Z. Tan, P. Sekatski, R. L. Urbanke, R. Renner, N. Sangouard, J-D. Bancal     
Nature 607, 682–686 (2022)     
(Article, Preprint)

Micromotion minimisation by synchronous detection of parametrically excited motion

D. P. Nadlinger, P. Drmota, D. Main, B. C. Nichol, G. Araneda, R. Srinivas, L. J. Stephenson, C. J. Ballance, D. M. Lucas     
(Preprint)

Precision measurement of the 43Ca+ nuclear magnetic moment

R. K. Hanley, D. T. C. Allcock, T. P. Harty, M. A. Sepiol, D. M. Lucas     
Phys. Rev. A 104, 052804     
(Article, Preprint)

Universal hybrid quantum computing in trapped ions

R. T. Sutherland and R. Srinivas     
Phys. Rev. A 104, 032609     
(ArticlePreprint)

 

2020

An optically heated atomic source for compact ion trap vacuum systems

S. Gao, W. J. Hughes, D. M. Lucas, T. G. Ballance, and J. F. Goodwin     
Rev. Sci. Instrum. 92, 033205 (2021)     
(Article, Preprint)

Effects of cavity birefringence in polarisation-encoded quantum networks

E. Kassa, W. Hughes, S. Gao and J. F. Goodwin     
New J. Phys. 25, 013004 (2023)
(Article, Preprint)

Benchmarking a high-fidelity mixed-species entangling gate

A. C. Hughes, V. M. Schäfer, K. Thirumalai, D. P. Nadlinger, S. R. Woodrow, D. M. Lucas, C. J. Ballance     
Phys. Rev. Lett. 125, 080504 (2020)    
(Article, Preprint, Synopsis in "Physics")

 

2019

High-rate, high-fidelity entanglement of qubits across an elementary quantum network

L. J. Stephenson, D. P. Nadlinger, B. C. Nichol, S. An, P. Drmota, T. G. Ballance, K. Thirumalai, J. F. Goodwin, D. M. Lucas, C. J. Ballance     
Phys. Rev. Lett. 124, 110501 (2020)    
(Article, Preprint, "Physics World" article)

Probing qubit memory errors at the part-per-million level

M. A. Sepiol, A. C. Hughes, J. E. Tarlton, D. P. Nadlinger, T. G. Ballance, C. J. Ballance, T. P. Harty, A. M. Steane, J. F. Goodwin and D. M. Lucas     
Phys. Rev. Lett. 123, 110503 (2019)
(Article, Preprint)

 

2018

Magnetic field stabilization system for atomic physics experiments

B. Merkel, K. Thirumalai, J. E. Tarlton, V. M. Schäfer, C. J. Ballance, T. P. Harty, D. M. Lucas     
Rev. Sci. Instrum., 90, 044702 (2019)   
(Article, Preprint)

 

2017

A short response-time atomic source for trapped ion experiments

T. G. Ballance, J. F. Goodwin, B. Nichol, L. J. Stephenson, C. J. Ballance, D. M. Lucas     
Rev. Sci. Instrum., 89, 053102 (2018)   
(Article, Preprint)

Fast quantum logic gates with trapped-ion qubits

V. M. Schäfer, C. J. Ballance, K. Thirumalai, L. J. Stephenson, T. G. Ballance, A. M. Steane and D. M. Lucas     
Nature, Vol. 555, pp. 75-78     
(Article, Preprint, Nature "News & Views" by Prof. Tobias Schaetz)

The effect of atomic response time in the theory of Doppler cooling of trapped ions

H. Janacek, A. M. Steane, D. M. Lucas, and D. N. Stacey     
Journal of Modern Optics, Vol. 65, pp. 577-584     
(Article, Preprint)

 

2016

High-fidelity trapped-ion quantum logic using near-field microwaves

T. P. Harty, M. A. Sepiol, D. T. C. Allcock, C. J. Ballance, J. E. Tarlton, D. M. Lucas     
Phys. Rev. Lett. 117, 140501 (2016)    
(Article, Preprint)

High-fidelity spatial and polarization addressing of 43Ca+ qubits using near-field microwave control

D. P. L. Aude Craik, N. M. Linke, M. A. Sepiol, T. P. Harty, J. F. Goodwin, C. J. Ballance, D. N. Stacey, A. M. Steane, D. M. Lucas, and D. T. C. Allcock     
Phys. Rev. A 95, 022337 (2017)   
(Article, Preprint)

 

2015

High-fidelity quantum logic gates using trapped-ion hyperfine qubits

C. J. Ballance, T. P. Harty, N. M. Linke, M. A. Sepiol, D. M. Lucas     
Phys. Rev. Lett. 117, 060504     
(Article, Preprint)

Dark-resonance Doppler cooling and high fluorescence in trapped Ca-43 ions at intermediate magnetic field

D. T. C. Allcock, T. P. Harty, M. A. Sepiol, H. A. Janacek, C. J. Ballance, A. M. Steane, D. M. Lucas, D. N. Stacey     
New J. Phys., Vol. 18, pp. 023043     
(Article, Preprint)

Optical injection and spectral filtering of high-power UV laser diodes

V. M. Schäfer, C. J. Ballance, C. J. Tock, D. M. Lucas     
Opt. Lett., Vol. 40, pp. 4265-4268     
(Article, Preprint)

Hybrid quantum logic and a test of Bell's inequality using two different atomic species

C. J. Ballance, V. M. Schäfer, J. P. Home, D. J. Szwer, S. C. Webster, D. T. C. Allcock, N. M. Linke, T. P. Harty, D. P. L. Aude Craik, D. N. Stacey, A. M. Steane, D. M. Lucas     
Nature, Vol. 528, pp. 384–386     
(Article, Preprint, Nature "News & Views" by Prof. Tobias Schaetz, "Physics World" Top 10 Breakthroughs of 2016)

 

2014

High-fidelity two-qubit quantum logic gates using trapped calcium-43 ions

C. J. Ballance, T. P. Harty, N. M. Linke, D. M. Lucas     
(Preprint)

High-fidelity preparation, gates, memory and readout of a trapped-ion quantum bit

T. P. Harty, D. T. C. Allcock, C. J. Ballance, L. Guidoni, H. A. Janacek, N. M. Linke, D. N. Stacey, D. M. Lucas     
Phys. Rev. Lett., Vol. 113, Issue 22, pp. 220501     
(Article, Preprint, "Viewpoint: Trapped Ions Make Impeccable Qubits" by Prof. Jungsang Kim, phys.org, Nature - research highlights: "Qubits come close to perfection")

 

2013

Pulsed force sequences for fast phase-insensitive quantum gates in trapped ions

A. M. Steane, G. Imreh, J. P. Home, D. Leibfried     
New J. Phys., Vol. 16, pp. 053049     
(Article, Preprint)

Injection locking of two frequency-doubled lasers with 3.2 GHz offset for driving Raman transitions with low photon scattering in 43Ca+

N. M. Linke, C. J. Ballance, D. M. Lucas     
Optics Letters, Vol. 38, Issue 23, pp. 5087-5089     
(Article, Preprint)

Microwave control electrodes for scalable, parallel, single-qubit operations in a surface-electrode ion trap

D. P. L. Aude Craik, N. M. Linke, T. P. Harty, C. J. Ballance, D. M. Lucas, A. M. Steane, D. T. C. Allcock     
Applied Physics B, Vol. 114, Issue 1-2, pp. 3-10     
(Article, Preprint)

Experimental recovery of a qubit from partial collapse

J. A. Sherman, M. J. Curtis, D. J. Szwer, D. T. C. Allcock, G. Imreh, D. M. Lucas, A. M. Steane     
Phys. Rev. Lett., Vol. 111, Issue 18, pp. 180501     
(Article, Preprint, phys.org, gaianews.it)

 

2012

Injection locking of violet laser diodes with a 3.2 GHz offset frequency for driving Raman transitions in 43Ca+

B. C. Keitch, N. R. Thomas, D. M. Lucas     
Optics Letters, Vol. 38, Issue 6, pp. 830-832     
(Article, Preprint)

A microfabricated ion trap with integrated microwave circuitry

D. T. C. Allcock, T. P. Harty, C. J. Ballance, B. C. Keitch, N. M. Linke, D. N. Stacey, D. M. Lucas     
Applied Physics Letters, Vol. 102, No. 4, pp. 044103     
(Article, Preprint)

 

2011

Background-free detection of trapped ions

N. M. Linke, D. T. C. Allcock, D. J. Szwer, C. J. Ballance, T. P. Harty, H. A. Janacek, D. N. Stacey, A. M. Steane, D. M. Lucas     
Applied Physics B, Vol. 107, Issue 4, pp. 1175-1180     
(Article, Preprint)

Reduction of heating rate in a microfabricated ion trap by pulsed-laser cleaning

D. T. C. Allcock, L. Guidoni, T. P. Harty, C. J. Ballance, M. G. Blain, A. M. Steane, D. M. Lucas     
New J. Phys., Vol. 13, pp. 123023     
(Article, Preprint)

Heating rate and electrode charging measurements in a scalable, microfabricated, surface-electrode ion trap

D. T. C. Allcock, T. P. Harty, H. A. Janacek, N. M. Linke, C. J. Ballance, A. M. Steane, D. M. Lucas, R. L. Jarecki Jr., S. D. Habermehl, M. G. Blain, D. Stick, D. L. Moehring     
Applied Physics B, Vol. 107, Issue 4, pp. 913-919     
(Article, Preprint)

 

2010

Keeping a single qubit alive by experimental dynamic decoupling

D. J. Szwer, S. C. Webster, A. M. Steane and D. M. Lucas     
J. Phys. B: At. Mol. Opt. Phys., Vol. 44, No. 2, pp. 025501     
(Article, Preprint)

 

2009

Implementation of a symmetric surface electrode ion trap with field compensation using a modulated Raman effect

D. T. C. Allcock, J. A. Sherman, D. N. Stacey, A. H. Burrell, M. J. Curtis, G.Imreh, N. M. Linke, D. J. Szwer, S. C. Webster, A. M. Steane and D. M. Lucas     
New J. Phys., Vol. 12, pp. 053026     
(Article, Preprint)

Scalable simultaneous multi-qubit readout with 99.99% single-shot fidelity

A. H. Burrell, D. J. Szwer, S. C. Webster and D. M. Lucas     
Phys. Rev. A, Vol. 81, Issue 4, pp. 040302     
(Article, Preprint)

 

2008

Memory coherence of a sympathetically cooled trapped-ion qubit

J. P. Home, M. J. McDonnell, D. J. Szwer, B. C. Keitch, D. M. Lucas, D. N. Stacey, and A. M. Steane     
Phys. Rev. A., Vol. 79, Issue 5, pp. 050305     
(Article, Preprint)

Optical Bloch equations with multiply-connected states

D.N. Stacey, D.T.C. Allcock, D.M. Lucas, D.J. Szwer, S.C. Webster     
J. Phys. B., Vol. 41, No. 8, pp. 085502     
(Article)

High-fidelity readout of trapped-ion qubits

A. H. Myerson, D. J. Szwer, S. C. Webster, D. T. C. Allcock, M. J. Curtis, G. Imreh, J. A. Sherman, D. N. Stacey, A. M. Steane, and D. M. Lucas     
Phys. Rev. Lett., Vol. 100, Issue 20, pp. 200502     
(Article, Preprint)

 

2007

A long-lived memory qubit on a low-decoherence quantum bus

D. M. Lucas, B. C. Keitch, J. P. Home, G. Imreh, M. J. McDonnell, D. N. Stacey, D. J. Szwer and A. M. Steane     
(Preprint)

 

2006

Context, spacetime loops and the interpretation of quantum mechanics

A. M. Steane     
J. Phys. A: Math. Theor., Vol. 40, No. 12, pp. 3223-3243     
(Article, Preprint)

Long-lived mesoscopic entanglement outside the Lamb-Dicke regime

M. J. McDonnell, J. P. Home, D. M. Lucas, G. Imreh, B. C. Keitch, D. J. Szwer, N. R. Thomas, S. C. Webster, D. N. Stacey, A. M. Steane     
Phys. Rev. Lett., Vol. 98, Issue 6, pp. 063603     
(Article, Preprint)

Deterministic entanglement and tomography of ion spin qubits

J. P. Home, M. J. McDonnell, D. M. Lucas, G. Imreh, B. C. Keitch, D. J. Szwer, N. R. Thomas, S. C. Webster, D. N. Stacey, A. M. Steane     
New J. Phys., Vol. 8, pp. 188     
(Article, Preprint)

 

2004

How to build a 300 bit, 1 Giga-operation quantum computer

A. M. Steane     
Quantum Information and Computation, Vol. 7, No.3, pp. 171-183     
(Article, Preprint)

Electrode configurations for fast separation of trapped ions

J. P. Home, A. M. Steane     
Quantum Information and Computation, Vol. 6, Issue 4, pp. 289-325     
(Article, Preprint)

Laser linewidth effects in quantum state discrimination by electromagnetically induced transparency

M. J. McDonnell, D. N. Stacey, A. M. Steane     
Phys. Rev. A, Vol. 70, Issue 5, pp. 053802     
(Article, Preprint)

Further quantum-gate methods using selective displacement of trapped ions

M. Sasura, A. M. Steane     
(Preprint)

 

2003

High-efficiency detection of a single quantum of angular momentum by suppression of optical pumping

M. J. McDonnell, J.-P. Stacey, S. C. Webster, J. P. Home, A. Ramos, D. M. Lucas, D. N. Stacey, A. M. Steane     
Phys. Rev. Lett., Vol. 93, Issue 15, pp. 153601     
(Article)

Isotope-selective photo-ionization for calcium ion trapping

D. M. Lucas, A. Ramos, J. P. Home, M. J. McDonnell, S. Nakayama, J.-P. Stacey, S. C. Webster, D. N. Stacey, A. M. Steane     
Phys. Rev. A, Vol. 69, Issue 1, pp. 012711     
(Article, Preprint)

Oxford ion-trap quantum computing project

D. M. Lucas, C. J. S. Donald, J. P. Home, M. J. McDonnell, A. Ramos, D. N. Stacey, J.-P. Stacey, A. M. Steane, S. C. Webster     
Philos. Transact. A Math Phys Eng Sci. 361, 1401-8     
(Article)

Extracting entropy from quantum computers

A. M. Steane     
Ann. Henri Poincare 4 supplement 2, pp. 799-809     
(Article)

 

2002

Fast quantum logic by selective displacement of hot trapped ions

M. Sasura, A. M. Steane     
Phys. Rev. A, Vol. 67, Issue 6, pp. 062318     
(Article, Preprint)

Overhead and noise threshold of fault-tolerant quantum error correction

A. M. Steane     
Phys. Rev. A, Vol. 68, Issue 4, pp. 042322     
(Article, Preprint)

Quantum computer architecture for fast entropy extraction

A. M. Steane     
Quantum Information and Computation 2, pp. 297-306     
(Article, Preprint)

 

2001

Development of a linear ion trap for quantum computing

D. M. Lucas     
Proc. First Int. Conf. on Experimental Implementation of Quantum Computation, pp. 91-98     
(Article)

 

2000

Quantum computing with trapped ions, atoms and light

A. M. Steane, D.M. Lucas     
Fortschritte der Physik, Vol. 48, Issue 9-11, pp. 839–858     
(Preprint)

Quantum computing and error correction

A. M. Steane     
(Preprint)

Search for correlation effects in linear chains of trapped Ca+ ions

C. J. S. Donald, D. M. Lucas, P. A. Barton, M. J. McDonnell, J. P. Stacey, D. A. Stevens, D. N. Stacey, A. M. Steane     
Europhys. Lett. 51, pp. 388-394     
(Article, Preprint)

Speed of ion-trap quantum information processors

A. M. Steane, C. F. Roos, D. Stevens, A. Mundt, D. Leibfried, F. Schmidt-Kaler, R. Blatt     
Phys. Rev. A, Vol. 62, Issue 4, pp. 042305     
(Article, Preprint)

 

1999

Measurement of the lifetime of the 3d 2D5/2 state in 40Ca+

P. A. Barton, C. J. S. Donald, D. M. Lucas, D. A. Stevens, A. M. Steane, D. N. Stacey     
Phys. Rev. A, Vol. 62, Issue 3, pp. 032503     
(Article, Preprint)

 

1998

Simple experimental methods for trapped-ion quantum processors

D. Stevens, J. Brochard, A. M. Steane     
Phys. Rev. A Vol. 58, Issue 4, pp. 2750     
(Article, Preprint)

 

1997

Quantum Computing

A. M. Steane     
Rep. Prog. Phys., Vol. 61, pp. 117-173     
(Article, Preprint)


Space, time, parallelism and noise requirements for reliable quantum computing

A. M. Steane     
Fortsch.Phys., Vol. 46, pp. 443     
(Preprint)

 

1996

Active stabilisation, quantum computation and quantum state synthesis

A. M. Steane     
Phys.Rev.Lett., Vol. 78, Issue 11, pp. 2252-2255     
(Article, Preprint)

The ion trap quantum information processor

A. M. Steane     
Applied Physics B, Vol. 64, Issue 6, pp. 623-643     
(Article, Preprint)

Simple quantum error correcting codes

A. M. Steane     
Phys.Rev. A, Vol. 54, Issue 6, pp. 4741     
(Article, Preprint)

 

1995

Multiple particle interference and quantum error correction

A. M. Steane     
Proc. R. Soc. Lond. A, Vol. 452, pp. 2551-2577     
(Article, Preprint)

Error correcting codes in quantum theory

A. M. Steane     
Phys.Rev.Lett., Vol. 77, Issue 5, pp. 793-797     
(Article)