Robust manipulation of magnetism in dilute magnetic semiconductor (Ga, Mn)As by organic molecules

We firstly demonstrated the organic molecular manipulation of the magnetism of (Ga, Mn)As. Mn-doped GaAs thin films with various thicknesses were grown by low-temperature molecular-beam epitaxy (LT-MBE), and organic charge-transfer molecules were deposited on the surface of (Ga, Mn)As films by either solution-based self-assembly or vacuum thermal evaporation, which led to large carrier density modulation, and significant changes in the Curie temperature (T
c
) and magnetization (M
s
). Electron donor (acceptor) molecules were found to decrease (increase) both T
c
and M
s
. Moreover, through proper preparation of the (Ga, Mn)As surface, self-assembled monolayer (SAM) patterns of organic molecules with sub-75 nanometer line width were successfully created via dip-pen nanolithography (DPN). These results could open a new pathway to control nano-scale manipulation of magnetism in DMS, with potential applications in reconfigurable, non-volatile and hybrid molecular nano-spintronics.