https://doi.org/10.1140/epjd/e2008-00115-2
Vector Cooper pairs and coherent-population-trapping-like states in ensemble of interacting fermions
1
Institute of Laser Physics SB RAS, Novosibirsk, 630090, Russia
2
Novosibirsk State University, Novosibirsk, 630090, Russia
3
Novosibirsk State Technical University, Novosibirsk, 630092, Russia
Corresponding author: a llf@laser.nsc.ru
Received:
18
February
2008
Published online:
13
June
2008
Using the standard Hamiltonian of the BCS theory, we show that in an ensemble of interacting fermions with the spin 1/2 there exist coherent states |NC〉, which nullify the Hamiltonian of the interparticle interaction (scattering). These states have an analogy with the well-known in quantum optics the coherent population trapping (CPT) effect. The structure of these CPT-like states corresponds to Cooper pairs with the total spin S = 1. The found states have a huge degree of degeneracy and carry a macroscopic magnetic moment, that allows us to construct a new model of the magnetism connected with the delocalized electrons in metals (conductors). A principal possibility to apply the obtained results to the superfluid 3He is also demonstrated.
PACS: 42.50.Gy – Effects of atomic coherence on propagation, absorption, and amplification of light; electromagnetically induced transparency and absorption / 74.20.Fg – BCS theory and its development / 75.10.-b – General theory and models of magnetic ordering / 67.30.H- – Superfluid phase of 3He
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2008
