Dissipative Quantum Tunneling and Magnetic Response of a Single Electron in a Four-Well Potential

Abstract

We study dissipative tunneling of a single electron in a four-well semiconductor nanostructure threaded by a magnetic flux. The system under consideration allows us to investigate an influence of dissipation and irreversibility on two fundamental quantum-interference phenomena: tunneling and the Aharonov–Bohm effect at once. We calculate the steady-state magnetic moment of the particle (orbital paramagnetism) and study its temperature dependence. The existence of orbital paramagnetism is evidence for electron persistent tunneling between quantum dots as well as for the conservation of quantum coherence in the thermodynamic-equilibrium state.