Low energy properties of identical and strongly correlated particles
Article first published online: 31 AUG 2010
Copyright © 1996 WILEY-VCH Verlag GmbH & Co. KGaA
Annalen der Physik
Volume 508, Issue 5, pages 401–445, July 1996
How to Cite
Häusler, W. (1996), Low energy properties of identical and strongly correlated particles. Ann. Phys., 508: 401–445. doi: 10.1002/andp.2065080502
- Issue published online: 31 AUG 2010
- Article first published online: 31 AUG 2010
- Manuscript Accepted: 16 FEB 1996
- Manuscript Revised: 12 JAN 1996
- Manuscript Received: 17 OCT 1995
- Strong correlations;
- Spin excitations;
- Rotational tunneling;
Interesting qualitative consequences can arise from the quantum mechanical identity among strongly correlated particles that carry spin. This is demonstrated for properties connected with the low energy excitations in molecular and electronic systems. Spatial permutations among the identical particles are used as the key features.
The particular behaviour of rotational tunneling molecules or molecular parts under the influence of dissipation are discussed together with the consequences arising for conversion transitions. The relationship between the thermal shifting of the tunneling line and the conversion rate at low and at elevated temperatures is explicated. The valuable information, that can be extracted from the conversion behaviour after isotopical substitution, is explained in detail. At low temperatures qualitative changes are predicted for the conversion rate by deuteration. Weakly hindered rotors show, also experimentally, drastic isotopic effects.
The second part is devoted to finite systems of strongly interacting electrons that appear in semi-conductor nano-structures. The lowest excitation energies are strongly influenced by the interaction. They can be understood and determined starting from the limit of crystallized electrons by introducing localized many particle ‘pocket states’. The energy levels show multiplet structure, in agreement with numerical results. The total electron spin, associated with the low energy excitations, is crucially important for the nonlinear transport properties through quantum dots. It allows for instance to explain the appearance of negative differential conductances.