Principal Investigator: Priv.-Doz. Dr. habil. Oleksandr Dobrovolskiy

Scientific Staff: Praedoc Barbora Budinská, Dr. Sebastian Knauer

The two key cases of nondissipating motion in nature are the propagation of light (and other electromagnetic waves) in vacuum and the flow of electrical current in superconductors. In the second case, the energy dissipation is forbidden by the existence of a coherent quantum state of the condensate of electric charge carries (Cooper pairs). While propagating light interacts with matter and gravitational waves and represents the basis for optical and photonic devices, the frictionless flow of supercurrent interferes with nanosize objects in the superconductor such as tunnel barriers, surfaces, or the so-called fluxons (vortices) which are quantized magnetic flux tubes induced by an applied current, a magnetic field, or fluctuations.

Publications

• Fast Dynamics of Vortices in Superconductors
  O. V. Dobrovolskiy
  in Encyclopedia of Condensed Matter Physics (ed. V. M. Fomin), Springer, 2023
• Quantum Escape
  B. Leridon, H. Suderow, S. Nicaud, J. Aarts, S. Bending, O. Dobrovolskiy, A. Hassanien, W. Lang, F. Tafuri, A. Zalevski
  Ricochet, Tourtour, 2022, ISBN 978-2352633907
• Rising speed limits for fluxons via edge quality improvement in wide MoSi thin films

  B. Budinska, B. Aichner, D. Yu. Vodolazov, M. Yu. Mikhailov, F. Porrati, M. Huth, A. V. Chumak, W. Lang, and O. V. Dobrovolskiy

  Phys. Rev. Appl. 17, 034072 (2022)
• Ultra-fast vortex motion in a direct-write Nb-C superconductor
  O. V. Dobrovolskiy, D. Yu. Vodolazov, F. Porrati, R. Sachser, V. M. Bevz, M. Yu. Mikhailov, A. V. Chumak, and M. Huth
  Nat. Commun. 11, 3291 (2020)
• Vortices and non-equilibrium phenomena in superconductors
  O.V. Dobrovolskiy and A.I. Bezuglyj (Guest Editors)
  Low Temp. Phys. 46, 307-308 (2020)
• Moving flux quanta cool superconductors by a microwave breath 
  O. V. Dobrovolskiy, C. Gonzalez-Ruano, A. Lara, R. Sachser, V. M. Bevz, V. A. Shklovskij, A. I. Bezuglyj, R. V. Vovk, M. Huth, and F. G. Aliev
  Commun. Phys. 3, 64 (2020)
• Upper frequency limits for vortex guiding and ratchet effects
  O. V. Dobrovolskiy, E. Begun, V. M. Bevz, R. Sachser, and M. Huth
  Phys. Rev. Appl. 13, 024012 (2020)
• Different single photon response of wide and narrow superconducting MoSi strips
  Yu. P. Korneeva, N. N. Manova, I. N. Florya, M. Yu. Mikhailov, O. V. Dobrovolskiy, A. A. Korneev, D. Yu. Vodolazov 
  Phys. Rev. Appl. 13, 024011 (2020)
• Fast dynamics of guided magnetic flux quanta
  O. V. Dobrovolskiy, V. M. Bevz, E. Begun, R. Sachser, R. V. Vovk, and M. Huth,
  Phys. Rev. Appl. 11, 054064 (2019)
• Local flux-flow instability in superconducting films near Tc
  A. I. Bezuglyj, V. A. Shklovskij, R. V. Vovk, V. M. Bevz, M. Huth, and O. V. Dobrovolskiy,
  Phys. Rev. B 99, 174518 (2019) 
  
• Microwave radiation detection with an ultra-thin and free standing superconducting niobium nano-helix
  S. Lösch, A. Alfonsov, O. V. Dobrovolskiy, R. Keil, V. Engemaier, S. Baunack, G. Li, O. G. Schmidt, and D. Bürger,
  ACS Nano 13, 2948 (2019)
• Reduction of microwave loss by mobile fluxons in grooved Nb films
  O. V. Dobrovolskiy, R. Sachser, V. M. Bevz, A. Lara, F. G. Aliev, V. A. Shklovskij, A. I. Bezuglyj, R. V. Vovk, and M. Huth,
  Phys. Stat. Sol. - Rap. Res. Lett. 13, 1800223 (2019)
• Microwave emission from superconducting vortices in Mo/Si superlattices
  O. V. Dobrovolskiy, V. M. Bevz, M. Yu. Mikhailov, O. I. Yuzephovich, V. A. Shklovskij, R. V. Vovk, M. I. Tsindlekht, R. Sachser, and M. Huth,
  Nature Commun. 9, 4927 (2018)
• Radiofrequency generation by coherently moving fluxons
  O. V. Dobrovolskiy, R. Sachser, M. Huth, V. A. Shklovskij, R. V. Vovk, V. M. Bevz, and M. Tsindlekht,
  Appl. Phys. Lett. 112, 152601 (2018)