Persistent and radiation-induced currents in distorted quantum rings

Persistent and Radiation-Induced Currents in Distorted Quantum Rings

Oscillatory persistent currents in self-assembled quantum rings.

We report the direct measurement of the persistent current carried by a single electron by means of magnetization experiments on self-assembled InAs/GaAs quantum rings. We measured the first Aharonov-Bohm oscillation at a field of 14 T, in perfect agreement with our model based on the structural properties determined by cross-sectional scanning tunneling microscopy measurements. The observed os...

Persistent spin currents in mesoscopic Heisenberg rings.

We show that at low temperatures T an inhomogeneous radial magnetic field with magnitude B gives rise to a persistent magnetization current around a mesoscopic ferromagnetic Heisenberg ring. Under optimal conditions, this spin current can be as large as gmicro(B)(T/ variant Planck's over 2pi )exp([-2pi(gmicro(B)B/delta)(1/2)], as obtained from leading-order spin-wave theory. Here g is the gyrom...

Persistent currents in carbon nanotubes based rings

Persistent currents in rings constructed from carbon nanotubes are investigated theoretically. After studying the contribution of finite temperature or quenched disorder on covalent rings, the complexity due to the bundle packing is addressed. The case of interacting nanotori and self-interacting coiled nanotubes are analyzed in details in relation with experiments.

Persistent currents in carbon nanotube based rings

Carbon nanotubes are micrometer-long hollow cylinders with nanometer scale radii, and electronic properties strongly depending on their geometrical helicity. As promising tools for building up nanoscale electronic devices, nanotubes also allow one to challenge the well established common theories of mesoscopic physics. Recently, many works of quantum transport in these systems have revealed puz...