Inverse Spin Hall Effect in Electron Beam Evaporated Topological Insulator Bi2Se3 Thin Film
Braj B Singh et al.
physica status solidi (RRL)–Rapid Research Letters 13 (3), 2018, 1800492
Spintronics exploiting pure spin current in ferromagnetic (FM)/heavy metals (HM) is a subject of intense research. Topological insulators having spin momentum locked surface states exhibit high spin–orbit coupling and thus possess a huge potential to replace the HM like Pt, Ta, W, etc. In this context, the spin pumping phenomenon in Bi2Se3/CoFeB bilayers has been investigated. Bi2Se3 thin films are fabricated by electron beam evaporation method on Si (100) substrate. In order to confirm the topological nature of Bi2Se3, low temperature magnetotransport measurement on a 30 nm thick Bi2Se3 film which shows 10% magnetoresistance (MR) at 1.5 K has been performed. A linear increase in MR with applied magnetic field indicates the presence of spin momentum‐locked surface states. A voltage has been measured at room temperature to quantify the spin pumping which is generated via inverse spin Hall effect (ISHE). For the separation of spin rectification effects mainly produced by the FM CoFeB layer, in plane angular dependence of the dc voltage with respect to applied magnetic field has been measured. Our analysis reveals that spin pumping induced ISHE is the dominant contribution in the measured voltage.
Homepage of
Prof. Dr. Subhankar Bedanta
Professor in Physics
Chief-Coordinator of Centre for Interdisciplinary Sciences (CIS), NISER
Laboratory for Nanomagnetism and Magnetic Materials (LNMM)
National Institute of Science Education and Research
ABOUT US
We are a group (feelings is like a family) who believes in hard work, sincerity, discipline. We enjoy our work and have a lot of fun in each of our group activities.
We are working on various research topics in nanomagnetism and spintronics viz.
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Magnetic domains and domain wall dynamics
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Superferromagnetism,
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Magnetic Antidot Lattices (MALs)
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Antiferromagnetic Spintronics
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Topological Insulators
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Flexible spintronics
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Skyrmionics in thin films
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Organic spintronics
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Ferrimagnetic spintronics
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Spin Pumping via Inverse spin Hall effect (ISHE).
We are always committed to contribute to the scientific community by our novel work.
We have published about 100 papers in different international journals of high repute like
Phys. Rev. Lett.; Phys. Rev. Applied, Phys. Rev. B; NPG Asia materials; ACS Applied Materials & Interfaces; Nanoscale; Scientific reports; Appl. Phys. Lett.; J. Mater. Chem. C; Advanced Quantum Technology; ACS Applied Nano Materials; J. Phys. Chem. C; Nanotechnology; Phys. Chem. Chem. Phys.; J. Appl. Phys., J. Phys. D- Appl. Phys., J. Magn. Magn. Mater., RSC advance, etc.
Our alumni
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Seven Ph.D students have already graduated (now postdocs at IIT Delhi; Université Paris-Saclay, France, THALES, France; University of Turin etc). Two Former PhD students Dr. Sougata Mallick and Dr. Srijani Mallik have recently joined SRM Institute of Science and Technology as faculty. Another former PhD student Dr. Koustuv Roy is working as an Assistant Professor Acharya Prafulla Chandra Roy Government College, West Bengal.
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Sixteen M.Sc. students have performed their final year MSc thesis (now working at several good places like University of California, USA; Università degli Studi di Torino, Italy; Kansas State University, USA; Martin Luther Universität Halle Wittenberg, Halle, Germany; Michigan State University, USA; University of New Mexico, USA; Johannes Gutenberg University of Mainz, Germany etc.)
Present Group: 3 post docs, 7 PhD students, 1 Int. PhD and 3 M.Sc. students.
Opportunities: Highly motivated students (both masters and PhD) and postdocs are always encouraged to join and work in our group.
Domain wall motion in out-of-plane magnetized antidot lattice arrays imaged by state-of-art Kerr microscopy
Power dependent inverse spin Hall effect (ISHE) of Si/CoFeB/IrOx trilayers
Our broad research area is to study the properties of magnetic materials in bulk and low dimension.
Our group focuses on the following research areas......
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Magnetic multilayers (inter-layer coupling effects)
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Epitaxial magnetic thin films (domain and domain wall dynamics)
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Organic spintronics
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Antiferromagnetic Spintronics
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Flexible Spintronics
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Superferromagnetism
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Patterned magnetic nanostructures (magnetic dots, anti-dots)
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Magnetic nanoparticles (interparticle interaction effects)
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Dzyaloshinskii Moriya interactions and study of Skyrmions (experiment and OOMMF simulations)
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Exchange Bias due to spin glass like interface
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2D magnetic materials
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Study of interface magnetism in MoS2/ferromgnetic heterostructures