Abstract:
Understanding the physics of interacting quantum many-body systems has
gained immense attention in recent years as this governs the behavior of a huge variety of materials, such as, quantum magnetic materials, organic conductors[1] and
charge transfer systems[2], multiferroics[3] and magnetoelectrics[4], conventional as
well as high-Tc superconductors[5], superfluids[6], Kondo lattices[7], Quantum Hall
systems[8] and many more. Such strongly correlated materials have potential applications in a range of phenomena, from electronic, energy and memory devices
to spin and quantum computing.
Systems in which electrons can wander almost freely, or, in other words, have
a large kinetic energy with respect to the Coulomb interactions between them,
can be dealt with the formalism of single particle quantum mechanics. However,
interactions cannot always be neglected. For instance, in a class of f-electron
systems, called heavy fermion systems,[9,10] in which the effective mass of the electrons are higher than their rest mass by several orders of magnitude. Thus, they
are no longer freely moving individual electrons as electronic correlations become
prominent. Still, many such interacting systems can be explained in the limits of
Fermi Liquid Theory [11,12], in which the collective behaviour of such heavy electrons resemble that of non-interacting fermions with renormalized heavier masses.
