Tomi H. Johnson

Room 318.6
Clarendon Laboratory
Parks Road
Oxford
OX1 3PU, UK

tomihjohnson@gmail.com
+44 1865 272388

Research Fellow at the Centre for Quantum Technologies, National University of Singapore

College Lecturer in Physics at Keble College, University of Oxford

I am a theoretical physicist with a broad range of interests, from cold atomic gases and many body physics, to quantum information and computing, and methods for simulating non-equilibrium stochastic and quantum processes.

Publications

T. J. Elliott and T. H. Johnson
Non-destructive probing of means, variances, and correlations of ultracold atomic system densities via qubit impurities
arXiv:1602.02579

T. H. Johnson, Y. Yuan, W. Bao, S. R. Clark, C. Foot, and D. Jaksch
Hubbard model for atomic impurities bound by the vortex lattice of a rotating BEC
arXiv:1512.09334

T. H. Johnson, F. Cosco, M. T. Mitchison, D. Jaksch, and S. R. Clark
Thermometry of arbitrary quantum systems via non-equilibrium work distributions
arXiv:1508.02992

D. Hangleiter, M. T. Mitchison, T. H. Johnson, M. Bruderer, M. B. Plenio, and D. Jaksch
Non-destructive selective probing of phononic excitations in a cold Bose gas using impurities
Phys. Rev. A 91, 013611 (2015); arXiv:1411.0688

T. H. Johnson, T. J. Elliott, S. R. Clark, and D. Jaksch
Capturing exponential variance using polynomial resources: applying tensor networks to non-equilibrium stochastic processes
Phys. Rev. Lett. 114, 090602 (2015); arXiv:1410.3319

D. Lu, J. Biamonte, J. Li, H. Li, T. H. Johnson, V. Bergholm, M. Faccin, Z. Zimborás, R. Laflamme, J. Baugh, and S. Lloyd
Chiral Quantum Walks
arXiv:1405.6209

T. H. Johnson, S. R. Clark, and D. Jaksch
What is a quantum simulator?
EPJ Quantum Technology 1, 10 (2014); arXiv:1405.2831
News: Several scientific news outlets, including AlphaGalileo, Phys.org and Science Daily, as well as journal (Springer Select, EPJ Quantum Technologies Highlight) and institution (CQT Highlight) highlights. See its Altimetric Profile.

M. Faccin, P. Migdał, T. H. Johnson, J. Biamonte, and V. Bergholm
Community Detection in Quantum Complex Networks
Phys. Rev. X 4, 041012 (2014); arXiv:1310.6638
News: ISI Press Release.

M. Faccin, T. H. Johnson, J. Biamonte, S. Kais, and P. Migdał
Degree distribution in quantum walks on complex networks
Phys. Rev. X 3, 041007 (2013); arXiv:1305.6078

R. Walters, G. Cotugno, T. H. Johnson, S. R. Clark, and D. Jaksch
Ab initio derivation of Hubbard models for cold atoms in optical lattices
Phys. Rev. A 87, 043613 (2013); arXiv:1303.2213

T. H. Johnson, J. Biamonte, S. R. Clark, and D. Jaksch
Solving search problems by strongly simulating quantum circuits
Sci. Rep. 3, 1235 (2013); arXiv:1209.6010

P. Haikka, T. H. Johnson, and S. Maniscalco
Non-Markovianity of local dephasing channels and time invariant discord
Phys. Rev. A 87, 010103(R) (2013); arXiv:1203.6469

T. H. Johnson, M. Bruderer, Y. Cai, S. R. Clark, W. Bao, and D. Jaksch
Breathing oscillations of a trapped impurity in a Bose gas
Europhys. Lett. 98, 26001 (2012); arXiv:1111.6154

T. H. Johnson, S. R. Clark, M. Bruderer, and D. Jaksch
Impurity transport through a strongly interacting bosonic quantum gas
Phys. Rev. A 84, 023617 (2011); arXiv:1106.3650

M. Bruderer, T. H. Johnson, S. R. Clark, D. Jaksch, A. Posazhennikova, and W. Belzig
Phonon resonances in atomic currents through Bose-Fermi mixtures in optical lattices
Phys. Rev. A 82, 043617 (2010); arXiv:1007.3828

T. H. Johnson, S. R. Clark, and D. Jaksch
Dynamical simulations of classical stochastic systems using matrix product states
Phys. Rev. E 82, 036702 (2010); arXiv:1006.2639

T. H. Johnson
Understanding traffic jams using quantum algorithms
MPhys report (2009), pdf

Talks, visits, conferences

Talk given at the CCPQ Workshop on Dynamics of Complex Quantum Systems, Windsor (2015)
Title: Thermometry of arbitrary quantum systems via non-equilibrium work distributions: application to bosons in a lattice
Slides: Here

Invited talk given at the University College London (2014)
Title: Tensor networks vs. Monte Carlo for stochastic processes
Slides: Here

Invited talk given at the Quantum Frontiers in Networks Science Satellite at NetSci, Berkeley (2014)
Title: Quantum-style tensor network factorisation in stochastic networks
Slides: Here

Invited talk given at the Quantum Frontiers in Networks Science Satellite at NetSci, Berkeley (2014)
Title: Community detection in quantum networks
Slides: Here

Talk given at the Workshop on Quantum Computation and Complex Networks at ICQ, Waterloo (2013)
Title: Connecting quantum computation, topology and the efficiency of solving search problems using tensor networks
Slides: Here

Attended the Decoherence and Friends Workshop at IQC, Waterloo (2013)

Talk given at the Institute of Scientific Interchange, Torino (2013)
Title: Simulating classical stochastic processes using quantum-inspired network-based data compression
Slides: Here

Poster presented at the International Conference on Atomic Physics, Paris (2012)
Title: Breathing oscillations of a trapped impurity in a Bose gas

Poster presented at the Quantum Twin Workshop, Favignana, Sicily (2012)
Title: Quantum vs. classical – implications for numerics
Poster: Here

Attended the Bridging the Gap Mini-workshop, Oxford University (2012)

Academic visit to the Centre of Quantum Technologies, Singapore (2012)

Talk given at the Quantum Correlations and Information Flow in Ultracold Atomic Gases Workshop, Nottingham University (2012)
Title: Quantum probing of ultracold gases
Slides: Here

Poster presented at the Dynamics and Simulation of Ultra-Cold Matter Workshop, Windsor (2011)
Title: Dynamical simulations of classical stochastic systems using matrix product states
Poster: Here

Co-organised the Keble Networks Research Cluster Workshop, Keble College, Oxford (2011)

Poster presented at the Keble Networks Research Cluster Workshop, Keble College, Oxford (2011)
Title: Dynamical simulations of classical stochastic systems using matrix product states
Poster: Here

Academic visit to the Centre of Quantum Technologies, Singapore (2011)

Poster presented at the 14th Workshop on Quantum Information Processing, Singapore (2011)
Title: Dynamical simulations of classical stochastic systems using matrix product states
Poster: Here

Talk given to the Atomic and Laser Physics Sub-department, Oxford University (2010)
Title: Tensor networks and stochastic systems; using quantum methods to study traffic jams
Slides: Here

Courses taught

Tutor in Introduction to Quantum Information, Mathematical Institute, Oxford University (2015 - Present)

Tutor in Mathematical Methods, Keble College, Oxford University (2013 - Present)

Tutor in Condensed Matter Physics, Keble College, Oxford University (2011 - Present)

Teaching Assistant in Quantum Information Processing, Department of Physics, Oxford University (2011 - 2012)

Tutor in Quantum Mechanics and Information, Centre in Oxford, Stanford University (2011)

Tutor in Quantum, Atomic and Laser Physics, St. Anne's College, Oxford University (2010 - 2012)

Private tutor in Quantum and Classical Mechanics, and Mathematics (2006 - 2012)

Teaching qualifications

Qualification: Associate Fellow of the Higher Education Academy (2012)

Training: Developing Learning and Teaching, Learning Institute, Oxford University (2012)
Portfolio: Here

Training: Science, Technology, Engineering and Mathmatics (STEM) Ambassador, STEM Network (2011)

Training: Reading Series on Teaching, Learning Institute, Oxford University (2011)

Training: Teaching Practices in the Sciences, Learning Institute, Oxford University (2011)

Training: Graduate Training Day, Department of Physics, Oxford University (2010)

Other activity

I occasionaly sit on the Engineering and Physical Sciences Selection Panel for the Researcher Links and Instituional Links grands awarded by the British Council under the Newton Fund. Through the Newton Fund, the UK aims to use its strength in research and innovation to promote economic development and social welfare of partner countries.

I am a Review Editor for the journal Frontiers in Quantum Computing. This journal is open access, taking novel approaches to science publication such as (i) separating out the processes of verifying accuracy and determining impact, (ii) allowing interactive review with unlimited rounds of review, and (iii) publishing the names of the reviewers alongside an accepted manuscript.

In 2014 I was a Local Champion for the Evidence Information Service (EIS), interviewing MPs in advance of the EIS's formation. One part of the EIS will connect politicians with scientists within a rapid time frame. The other part will act more proactively, preparing parliamentary briefings about evidence-based issues.

I have previously, as a Science, Technology, Engineering and Mathmatics (STEM) Ambassador, assisted in school and university-run activities designed to enthuse young people in the STEM subjects. Please contact me if there is an activity I can assist you with.

I am also interested in exploring ways to communicate my research to the wider academic community that go beyond traditional journal articles and conference talks. For example, I am an administrator of a Facebook group of over 3,500 members regarding Quantum Information and Computing, and I have written articles for the Azimuth blog, including

Blog article: Quantum network science (part 1)

Blog article: Quantum network science (part 2)

Internal links:

>> Publications

>> Talks, visits, conferences

>> Courses taught

>> Teaching qualifications

>> Other activity

External links:

>> My Oxford University profile

(incl. u.graduate teaching page)

>> My Oxford group's webpage

>> My CQT profile

>> My Google Scholar profile

>> My Resarcher ID profile

>> My ResearchGate profile

>> My ArXiv submissions

>> My Azmiuth profile