Cold Fermionic Atoms in Two-Dimensional Traps -- Pairing versus Hund's   Rule
  The microscopic properties of few interacting cold fermionic atoms confined in a two-dimensional (2D) harmonic trap are studied by numerical diagonalization. For repulsive interactions, a strong shell structure dominates, with Hund's rule acting at its extreme for the mid-shell configurations. In the attractive case, odd-even oscillations due to pairing occur simultaneously with deformations in the internal structure of the ground states, as seen from pair correlation functions. 
M. Rontani, J. R. Armstrong, Y. Yu, S. {\AA}berg, S. M. Reimann