Anomalous magnetic properties of Mn-implanted InN thin films

Publication date: Available online 27 February 2016
Source:Thin Solid Films
Author(s): P.H. Chang, H.C. Chen, C.W. Lin, M.X. Lai, S.Y. Hong, M.J. Lee
Anomalous magnetic properties of C-axis-oriented Mn-implanted InN thin films on GaN/sapphire substrates are reported. X-ray diffraction analysis revealed Mn-implanted InN films of a high-quality crystal phase with Wurtzite structure. All samples show n-type conductivity by Hall measurements. The un-implanted InN/GaN/Al2O3 sample with a carrier concentration of 1.6×10²¹ cm⁻³ (n2D =8×10¹⁶ cm⁻²) exhibits increasing magnetization with decreasing temperature and did not appear superconductive above 1.8K. After Mn-ion implantation, the appearance of the Meissner effect with superconducting onset temperature near 2.4K was observed. The superconducting volume fraction χ is near 36% at 2.2K. Moreover, Type-II behavior was further characterized by field-dependent magnetization measurement.