Proximity induced band gap opening in topological-magnetic heterostructure (Ni80Fe20/p-TlBiSe2/p-Si) under ambient condition

Roshani Singh; Gyanendra Kumar Maurya; Vidushi Gautam; Rachana Kumar; Mahesh Kumar; K G Suresh; Brahmaranjan Panigrahi; Chandrasekhar Murapaka; Arbinda Haldar; Pramod Kumar

doi:10.1038/s41598-023-49004-5

Proximity induced band gap opening in topological-magnetic heterostructure (Ni₈₀Fe₂₀/p-TlBiSe₂/p-Si) under ambient condition

Sci Rep. 2023 Dec 15;13(1):22290. doi: 10.1038/s41598-023-49004-5.

Authors

Affiliations

¹ Spintronics and Magnetic Materials Laboratory, Department of Applied Sciences, Indian Institute of Information Technology Allahabad, Prayagraj, 211015, India.
² CSIR - Indian Institute of Toxicology Research, Lucknow, 226001, India.
³ CSIR-National Physical Laboratory, New Delhi, India.
⁴ Department of Physics, Indian Institute of Technology Bombay, Mumbai, 400076, India.
⁵ Department of Physics, Indian Institute of Technology Hyderabad, Kandi, 502284, Telangana, India.
⁶ Department of Materials Science and Metallurgical Engineering, Indian Institute of Technology Hyderabad, Kandi, Telangana, 502284, India.
⁷ Spintronics and Magnetic Materials Laboratory, Department of Applied Sciences, Indian Institute of Information Technology Allahabad, Prayagraj, 211015, India. pkumar@iiita.ac.in.

Abstract

The broken time reversal symmetry states may result in the opening of a band gap in TlBiSe₂ leading to several interesting phenomena which are potentially relevant for spintronic applications. In this work, the quantum interference and magnetic proximity effects have been studied in Ni₈₀Fe₂₀/p-TlBiSe₂/p-Si (Magnetic/TI) heterostructure using physical vapor deposition technique. Raman analysis shows the symmetry breaking with the appearance of A²_1u mode. The electrical characteristics are investigated under dark and illumination conditions in the absence as well as in the presence of a magnetic field. The outcomes of the examined device reveal excellent photo response in both forward and reverse bias regions. Interestingly, under a magnetic field, the device shows a reduction in electrical conductivity at ambient conditions due to the crossover of weak localization and separation of weak antilocalization, which are experimentally confirmed by magnetoresistance measurement. Further, the photo response has also been assessed by the transient absorption spectroscopy through analysis of charge transfer and carrier relaxation mechanisms. Our results can be beneficial for quantum computation and further study of topological insulator/ferromagnet heterostructure and topological material based spintronic devices due to high spin orbit coupling along with dissipationless conduction channels at the surface states.