
Courses: 



Address:  Niels Bohr Institute  
Universitetsparken 5  
DK2100 Copenhagen  
Denmark  
Mobile:  +45 23984007  
Email:  jens@fys.ku.dk  
Office:  D120  
Research area:
I am working on the theory of magnetic structures and excitations in condensed matter systems with localized moments, i.e. primarily systems containing ions from the series of the Lanthanides or the Actinides. I have written a monograph on the subject in collaboration with Allan Mackintosh: Jens Jensen and Allan R. Mackintosh: Rare Earth Magnetism: Structures and Excitations published by Clarendon Press, Oxford, England in 1991. Des McMorrow, Henrik Rønnow and I have edited the proceedings of Magnetism in Metals, a symposium in memory of Allan Mackintosh (193695), Copenhagen, August 2629, 1996 and published by The Royal Danish Academy of Sciences and Letters in Matematiskfysiske Meddelelser 45 (1997). Recent publications: U. B. Hansen, O. F. Syljuåsen, J. Jensen, T. K. Schãffer, C. R. Andersen, M. Boehm, J. A. RodriguezRivera, N. B. Christensen, K. Lefmann, Magnetic Bloch oscillations and domain wall dynamics in a nearIsing ferromagnetic chain, Nat. Commun. 13, 2547 (2022). Additional information: Supplement. R. ToftPetersen, T. B. S. Jensen, J. Jensen, M. v. Zimmermann, S. Sloth, F. W. Isaksen, N. B. Christensen, Y. Chen, K. Siemensmeyer, H. KawanoFurukawa, H. Takeya, A. B. Abrahamsen, and N. H. Andersen, Magnetoelastic phase diagram of TbNi_{2}B_{2}C, Phys. Rev. B 97, 224417 (2018). J. Jensen, J. Larsen, and U. B. Hansen, Comprehensive clustertheory analysis of the magnetic structures and excitations in CoCl_{2}·2H_{2}O, Phys. Rev. B 97, 024423 (2018). J. Larsen, T. K. Schäffer, U. B. Hansen, S. L. Holm, S. R. Ahl, R. ToftPetersen, J. Taylor, G. Ehlers, J. Jensen, H. M. Rønnow, K. Lefmann, and N. B. Christensen, Spin Excitations and Quantum Criticality in the Quasi OneDimensional IsingLike Ferromagnet CoCl_{2}·2D_{2}O in a Transverse Field, Phys. Rev. B 96, 174424 (2017). Recent seminars: Linear Response Theory and the Random Phase Approximation (International workshop on McPhase, Heinz Maier  Leibnitz Zentrum, Munich, 5.7. November 2014). Chiral spinwave excitations of the spin5/2 trimers in the langasite compound Ba_{3}NbFe_{3}Si_{2}O_{14} (TEMM, RutherfordAppleton Laboratory, Oxfordshire, June 2011). BoseEinstein condensation  in the spindimer system TlCuCl_{3}(?) (Niels Bohr Institute, Copenhagen, November 2009).
