Professor Steve Barnett

I have been an active researcher, primarily in the fields of quantum optics and quantum information, for more than 30 years (isn't it amazing how time flies).  I have very wide research interests and have worked on the non-classical properties of light and its interaction with matter (low-energy quantum electrodynamics), the quantum theory of optical phase and rotation angles, quantum communications and cryptography, quantum optics in material media, including optical forces and torques, quantum retrodiction (time-reversed quantum theory), optimal quantum measurements and the orbital angular momentum of light.  In my spare time (!) I also dabble in general relativity and in low temperature physics.  Throughout my career, I have always tried to work closely with experimental groups, partly because that is a way to stay true to the physics but principally because experimenters ask such interesting questions.  I firmly believe that a good theoretical explanation should be expressible on the back on the proverbial envelope and strive, wherever possible, for the neat and analytical solution to a problem.  I am the author of three graduate level textbooks: "Methods in Theoretical Quantum Optics" (written with Paul Radmore), "Quantum Information", and "Phase Space Methods for Degenerate Quantum Gases" (written with Bryan Dalton and John Jeffers), all published by Oxford University Press.

Contact details

Steve Barnett


Room 538, Kelvin Building, University of Glasgow, Glasgow G12 8QQ.

Selected publications

Phase Properties of the Quantized Single-Mode Electromagnetic Field, D.T. Pegg and S.M. Barnett; Physical Review A 39, 1665 (1989).

Quantization of the Electromagnetic Field in Dielectrics, Bruno Huttner and Stephen M. Barnett; Physical Review A 46, 4306 (1992).

Orbital Angular Momentum and Nonparaxial Light Beams, Stephen M. Barnett and L. Allen; Optics Communications, 110, 670 (1994).

Sum Rule for Modified Spontaneous Emission Rates, Stephen M. Barnett and Rodney Loudon; Physical Review Letters 77, 2444 (1996).

Optical state truncation, Stephen M. Barnett and David T. Pegg; Physical Review A, 60, 4965 (1999).

Master Equation for Retrodiction of Quantum Communication Signals, Stephen M. Barnett, David T. Pegg, John Jeffers and Ottavia Jedrkiewicz; Physical Review Letters 86, 2455 (2001).

Experimental demonstration of optimal unambiguous state discrimination, Roger B. M. Clarke, Anthony Chefles, Stephen M. Barnett and Erling Riis; Physical Review A 63, 040305(R) (2001).

Optical angular-momentum flux, Stephen M. Barnett, Journal of Optics B: Quantum and Semiclassical Optics 4, S7 (2002).

Interferometry below the Standard Quantum Limit with Bose-Einstein Condensates, J. A. Dunningham, K. Burnett and Stephen M. Barnett, Physical Review Letters 89, 150401 (2002).

Experimental Demonstration of Quantum Source Coding, Yasuyoshimi Mitsumori, John A. Vaccaro, Stephen M. Barnett, Erika Andersson, Atsushi Hasegawa, Masahiro Takeoka and Masahide Sasaki; Physical Review Letters 91, 217902 (2003).

Uncertainty principle for angular position and angular momentum, Sonja Franke-Arnold, Stephen M. Barnett, Eric Yao, Jonathan Leach, Johannes Courtial and Miles Padgett; New Journal of Physics 6, 103 (2004).

Quantum theory of friction, Stephen M. Barnett and James D. Cresser; Physical Review A 72, 022107 (2005).

Quasi-Intrinsic Angular Momentum and the Measurement of Its Spectrum, Roberta Zambrini and Stephen M. Barnett; Physical Review Letters 96, 113901 (2006).

On the electromagnetic force on a dielectric medium, Stephen M. Barnett and Rodney Loudon; Journal of Physics B: Atomic Molecular and Optical Physics 39, S671 (2006).

Momentum exchange between light and a single atom: Abraham or Minkowski?, E. A. Hinds and Stephen M. Barnett; Physical Review Letters 102, 050403 (2009).

Resolution of the Abraham-Minkowski Dilemma, Stephen M. Barnett; Physical Review Letters 104, 070401 (2010).

Optical Thomas-Reiche-Kuhn Sum Rules, Stephen M. Barnett and Rodney Loudon; Physical Review Letters, 108, 013601 (2012).

Electric-magnetic symmetry and Noether’s theorem, Robert P. Cameron and Stephen M. Barnett; New Journal of Physics 14, 123019 (2012).

Do Waves Carrying Orbital Angular Momentum Possess Azimuthal Linear Momentum?,  Fiona C. Speirits and Stephen M. Barnett; Physical Review Letters 111, 103602 (2013).

Beyond Landauer Erasure, Stephen M. Barnett and Joan A. Vaccaro; Entropy 15, 4956 (2013).

Quantum Optical State Comparison Amplifier, Electra Eleftheriadou, Stephen M. Barnett and  John Jeffers; Physical Review Letters 111, 213601 (2013). 


Methods in Theoretical Quantum Optics, Stephen M. Barnett and Paul M. Radmore (Oxford University Press, Oxford, 1997).

Quantum Information, Stephen M. Barnett (Oxford University Press, Oxford, 2009).

Phase Space Methods for Degenerate Quantum Gases, Bryan J. Dalton, John Jeffers, and Stephen M. Barnett (Oxford University Press, Oxford, 2015).