Selective‐area growth and magnetic reversals of ferromagnetic nanoclusters on semiconducting substrate for magnetic logic applications

Abstract

The use of selective‐area metal‐organic vapor phase epitaxy, which is our bottom‐up formation approach, to fabricate MnAs nanocluster composite arrays in which two nanoclusters are formed in close proximity at an angle of 120° and with a spatial gap of around 20 nm on GaAs (111)B substrates is reported in this paper. The magnetic reversals of the nanoclusters in the composite arrays are observed depending on the strengths and directions of the applied external magnetic fields at room temperature. The applied external magnetic fields for the magnetic reversals in one of the nanoclusters in the composites are possibly from 750 to 1000 Gauss (G). The characterization results obtained using magnetic force microscopy show that the magnetic reversals in the nanoclusters are independently controlled in nanocluster composites. Finally, we discuss the designing of the nanocluster size, shape, and arrangement to control the magnetization directions in the nanoclusters in the composites for possible application to magnetic logic operations based on the results of the magnetic reversals in the nanoclusters.