In close analogy to quantum electrodynamics, we derive a quantum field theory of Josephson plasma waves (JPWs) in layered superconductors (LSCs), which describes two types of interacting JPW bosonic quanta: one massive and the other almost-massless. We also calculate the amplitude of their decay and scattering. We propose a mechanism of enhancement of macroscopic quantum tunneling (MQT) in stacks of intrinsic Josephson-junctions (SIJJs). Due to the long-range interactions between many junctions in the LSCs, the calculated MQT escape rate Γ has a very nonlinear dependence on the number of junctions in the stack. This allows to quantitatively describe striking recent experiments in Bi2212 stacks.
@article{arxiv.cond-mat/0607479,
title = {Quantum Tera-Hertz electrodynamics in Layered Superconductors},
author = {Sergey Savel'ev and A. L. Rakhmanov and Franco Nori},
journal= {arXiv preprint arXiv:cond-mat/0607479},
year = {2007}
}