Orthogonality catastrophe

A priori, when the phonon relaxation is faster than the tunneling rates, thermodynamic equilibrium should hold at the temperature of the host reservoir. However, for the nano-junctions the local surface temperature may differ from the bulk equilibrium temperature. This is due to the Anderson orthogonality catastrophe (AOC)3 associated with interplay between the van der Waals and the electrostatic forces. The electron tunneling affects the overlap between differently shifted phonon ground states of the surface. The faster the tunneling rate, the closer is the phononic overlap to zero, and that hinders relaxation of the surface temperature. AOC presents the mechanism also affecting the thermal state of the electronic reservoir due to electron-phonon coupling. In Sec. 3, from comparison of our theoretical I-V curves at different electron-phonon temperatures and the experimental data [Park 2000] we infer that AOC exists. 

AOC Anderson orthogonality catastrophe [Anderson 1967], Zero overlap between ground states of surface vibrations e.g. the original state and charge induced configurations, where phonons are shifted by the tunneling electron. 

Shakeup represents a fundamental many-body effect that takes place in optical transitions in many-electron systems. In such systems, an absorption or emission of light is accompanied by electronic excitations in the final state of the transition. The most notable shakeup effect is the Anderson orthogonality catastrophe [5] in the electron gas when the initial and final states of the transition have very small overlap due to the readjustment of the Fermi sea electrons in order to screen the Coulomb potential of pho-toexcited core hole. Shakeup is especially efficient when the optical hole is immobilized, and therefore it was widely studied in conjunction with the Fermi edge singularity (FES) in metals [6-8] and doped semiconductor quantum wells [9-15]. Comprehensive reviews of FES and related issues can be found in Refs. [16,17]. 

Balents, L. 1999. Orthogonality catastrophes in carbon nanotubes, cond-mat/9906032. 

---