Johan Carlström

Postdoctoral research associate at the University of Massachusetts, Amherst.


Undergraduate studies:
2004-2009: Civilingenjör Teknisk fysik (Master, Engineering Physics) KTH, Stockholm.
Graduate studies:
2009-2014: Department of Theoretical Physics, Statistical Physics group, KTH. Thesis title: Multicomponent Superconductivity: Vortex Matter and Phase Transitions. Supervisor: Egor Babaev.

Jan. 2015 - present: Postdoctoral research associate at the Dept. of Physics, University of Massachusetts, Amherst, USA.

2014: The Wenner-Gren Foundations in Stockholm, 2 year postdoctoral fellowship.
2014: Stiftelsen Olle Engkvist Byggmästare, 2 year postdoctoral fellowship (declined).


  • Prediction of “Type-1.5 Superconductivity” resulting from proximity induced superconducting component.
  • Prediction of irregular vortex clusters resulting from multi-body intervortex forces.
  • Description of a new type of collective mode in multi-band superconductors with broken time-reversal symmetry, which describes simultaneous density- and phase-fluctuations.
  • Finding of a new topological excitation in superconductors with broken time-reversal symmetry: “chiral CP2 solitons”.
  • Prediction of superfluid states induced by thermal fluctuations in multicomponent systems.
  • Prediction of broken time-reversal symmetry induced from thermal fluctuations in frustrated multi-band superconductors.
  • First ever unbiased calculations of hole-propagation in paramagnetic environments.
  • Constructing of a spin-charge transformation of lattice fermions.


Physical review Letters
Physical review B
Nature Scientific Reports

02-01-2010 to 12-31-2012, University of Massachusetts, Amherst MA.

  • Lecturer, Graduate condensed matter theory (2013)
  • Teaching assistant, Graduate Statistical mechanics (2013), undergraduate Mathematical methods for physicists (2013), Graduate Quantum mechanics (2011, 2012)

Multi-Component and Strongly Correlated Superconductors, Stockholm 2016, Spin-charge transformation of lattice fermions.
Multi-Component and Strongly Correlated Superconductors, Stockholm 2016 (Invited talk), Spontaneous breakdown of time-reversal symmetry induced by thermal fluctuations.
APS March meeting, Baltimore 2016, Quantum walk in Degenerate Spin Environments.
Vortex IX, Rhodes 2015 (Invited talk), Spontaneous Breakdown of Time-Reversal Symmetry in frustrated Superconductors Induced by Thermal Fluctuations.
Vortex VIII, Rhodes 2013 (Invited talk), Type-1.5 superconductivity in systems with frustrated interband interaction.
International Conference on Mathematical Modelling in Physical Sciences, Prague 2013 (Invited talk),
Vortex-matter in multi-component superconductors.
APS March meeting, Boston 2012
, Length scales, collective modes, and type-1.5 regimes in
three-band superconductors.
Vortex VII, Rhodes 2011 (Invited talk), Non pairwise inter-vortex forces in multi-band superconductors.
APS March meeting, Dallas 2011, Properties of vortex clusters and inter-cluster interaction in type-II and type-1.5 two-band superconductors and type-I/type-II superconducting bilayers.
Vortex VI, Crete 2010 (Poster), Type-1.5 superconductivity in multi-band systems.
APS March meeting, Portland 2010, Type-1.5 superconductivity from interband Josephson coupling.

Nordita, Stockholm 2016, Quantum Walk in Degenerate Spin Environments.
University of Massachusetts, 2015, Spontaneous breakdown of time-reversal symmetry induced by thermal fluctuations
University of Massachusetts 2011, Multicomponent superconductors and type-1.5 superconductivity.

Current H-index: 8
Google scholar homepage:
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Prof. Egor Babaev, KTH,
Prof. Mats Wallin, KTH,
Prof. Boris Svistunov, University of Massachusetts,
Prof. Nikolai Prokof’ev, University of Massachusetts,