Fabrication and Investigation of Hybrid Device Consisting of Ferromagnetic Nanodots and Ga(Mn)As

The new hybrid device consisting of patterned array of Co nanodots on GaMnAs channel was fabricated and demonstrated to give a new functionality to control the transport properties of GaMnAs. Magnetic state of array of Co nanodots was observed with magnetic force microscopy (MFM) observation. The magnetic state of individual Co dots can be controlled by using a MFM tip. Different distribution of magnetic state of Co nanodots in an array structure resulted in an inhomogeneous magnetic field. Magnetic field induced by the array of nanodots leads to change in the transport properties of GaMnAs. This inhomogeneous magnetic field was regarded to act as an effective potential that can trap the spin polarized carriers in the GaMnAs system with giant Zeeman splitting.