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, @@@@@@@@@@@@@@@@ is work is performed under the CSIR-NLC rental pool project supported by the Nanotechnology Flagship Programme funded by NRF (SA). e support of EMU (Wits), DST/NRF Centre of Excellence in Strong materials and URC (Wits) towards this research is hereby acknowledged. We are thankful to D. Mtsuko, A. Naicker, and R. Erasmus for experimental assistance and N. J. Coville for useful discussions, AMS thanks SA-NRF (93549) and the URC/FRC of UJ. AdeS thanks the South African National Research Foundation

S. N. , performed device fabrication, transport measurements, and spectroscopic analysis. C.C. conducted detailed analysis of transport data. A.dS. performed chemical synthesis of the sample. E.F. did microscopic and elemental analysis of the samples. A.M.S. performed the magnetic characterization. S.B. developed the idea and designed the experimental method

, Supplementary information accompanies this paper at https