Enhanced Electron Pairing in a Lattice of Berry Phase Molecules


We show that electron hopping in a lattice of molecules possessing a Berry phase naturally leads to pairing. Our building block is a simple molecular site model inspired by C60, but realized in closer similarity with Na3. In the resulting model electron hopping must be accompanied by orbital operators, whose function is to switch on and off the Berry phase as the electron number changes. The effective hamiltonians (electron-rotor and electron-pseudospin) obtained in this way are then shown to exhibit a strong pairing phenomenon, by means of 1D linear chain case studies. This emerges naturally from numerical studies of small N -site rings, as well as from a BCS-like mean-field theory Email: manini@sissa.it Email: tosatti@sissa.it Email: doniach@drizzle.stanford.edu

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@inproceedings{Manini1994EnhancedEP, title={Enhanced Electron Pairing in a Lattice of Berry Phase Molecules}, author={Nicola Manini and Erio Tosatti and Sebastian Doniach}, year={1994} }