Macroscopic quantum tunneling of vortices in He II

Macroscopic Quantum Tunneling in Magnetic Nanostructures

Theoretical foundations of the problem of quantum spin tunneling in magnetic nanostructures are presented. Several model problems are considered in detail, including recent new results on tunneling in antiferromagnetic nanoparticles and topologically nontrivial magnetic structures in systems with reduced dimension.

Quantum terahertz electrodynamics and macroscopic quantum tunneling in layered superconductors.

We derive a quantum field theory of Josephson plasma waves (JPWs) in layered superconductors, which describes two types of interacting JPW bosonic quanta (one heavy and one lighter). We propose a mechanism of enhancement of macroscopic quantum tunneling (MQT) in stacks of intrinsic Josephson junctions. Because of the long-range interaction between junctions in layered superconductors, the calcu...

Resonance phenomena in Macroscopic Quantum Tunneling: the small viscosity limit

Abstract. We present a new theoretical approach to describe the quantum behavior of a macroscopic system interacting with an external irradiation field, close to the resonant condition. Here we consider the extremely underdamped regime for a system described by a double well potential. The theory includes both: transitions from one well to the other and relaxation processes. We simulate resonan...

Comment on Vortex Mass and Quantum Tunneling of Vortices

Vortex mass in Fermi superfluids and superconductors and its influence on quantum tunneling of vortices are discussed. The vortex mass is essentially enhanced due to the fermion zero modes in the core of the vortex: the bound states of the Bogoliubov qiasiparticles localized in the core. However, even with this enhancement, the contribution of the inertial term into the quantum tunneling expone...

Effects of dissipation and temperature on macroscopic quantum tunneling.