Researcher Asistant Professor Daniel Pęcak

IMiO Building 540
daniel.pecak@pw.edu.pl

RESEARCH

My scientific interests gravitate around strongly correlated fermionic systems, where the quantum correlations, including pairing, play a crucial role.

At the moment I'm involved in research on the so-called glitches, i. e. sudden speed-ups of the rotation of neutron stars. It is believed that the superfluidity of neutrons in the interior of a neutron star is the key to understand the physics of glitches. I apply microscopic nuclear theory to extract the effective parameters describing how the angular momentum can be stored in a form of vortices and transferred from the superfluid neutrons to the crust of the neutron star. The enormous numerical costs of such calculations can be met only be the largest supercomputers in the world.

Another area of physics that I'm devoted to is the few-body problems. I'm particularly fascinated with how the collective many-body phenomena manifest also in a limit of just several interacting particles.

SELECTED PUBLICATIONS

  1. D. Pęcak, M. F. Gajda, T. Sowiński, Two-flavour mixture of a few fermions of different mass in a one-dimensional harmonic trap, New J. Phys. 18, 013030 (2016) DOI: 10.1088/1367-2630/18/1/013030 arXiv: 1506.03592
  2. D. Pęcak, T. Sowiński, Few strongly interacting ultracold fermions in one-dimensional traps of different shapes, Phys. Rev. A 94, 042118 (2016) DOI: 10.1103/PhysRevA.94.042118 arXiv: 1606.02886
  3. D. Pęcak, A. S. Dehkharghani, N. T. Zinner, T. Sowiński, Four fermions in a one-dimensional harmonic trap: Accuracy of a variational-ansatz approach, Phys. Rev. A 95, 053632 (2017) DOI: 10.1103/PhysRevA.95.053632 arXiv: 1703.08720
  4. K. Lorek, D. Pęcak, E. G. Brown, A. Dragan, Extraction of genuine tripartite entanglement from the vacuum, Phys. Rev. A 90, 032316 (2014) DOI: 10.1103/PhysRevA.90.032316 arXiv: 1405.4449
  5. D. Pęcak, M. F. Gajda, T. Sowiński, Experimentally Accessible Invariants Encoded in Interparticle Correlations of Harmonically Trapped Ultra-cold Few-Fermion Mixtures, Phys. Rev. Lett. 103, 210403 (2009) DOI: 10.1007/s00601-017-1321-3 arXiv: 1703.08116

PROFILES