Thesis Title: Generation of Spin Polarization in Side-Gated InAs Quantum Point Contact. 

Thesis Advisor: Prof. Marc Cahay, Fellow, APS; Fellow, IEEE; Fellow, AAAS. 

PhD Work: My PhD dissertation explores the use of side-gated semiconductor quantum point contacts (QPCs) for generating strongly spin polarized current by purely electrical means in the absence of any applied magnetic field. At 4.2 Kelvin, an anomalous conductance plateau at conductance value, G = 0.5 × (2e2/h) was observed in our group [P. Debray et al., Nature Nanotechnology 4, 759 (2009)] in an asymmetrically biased InAs quantum point contact with in-plane side gates in the ballistic regime of transport. This is a clear experimental signature of spontaneous spin polarization in the narrow constriction of the QPC. A Non Equilibrium Green's Function (NEGF) approach revealed three ingredients which are necessary to create the spin polarization: an asymmetric lateral confinement, a lateral spin-orbit coupling induced by the lateral confining potential of the QPC, and a strong electron-electron interaction. In order to integrate such QPC devices to make all-electric spin valves, it is necessary to probe the sensitivity of these three ingredients to the bias difference between the two side gates that confine the electrons in the narrow channel. Towards that goal, my thesis shows that the anomalous conductance plateaus are quite robust and sustain for a range of asymmetric bias voltages. Also, a very systematic study has been conducted to explain the appearance of conductance anomalies ranging from 0.4 to 0.7×(2e2/h) for different biasing conditions. We propose as future work the possible use of QPC devices in series at elevated temperature as a mean to demonstrate an all- electric spin valve. 

Associate Professor in Physics, 2024 onward, National Institute of Technology Karnataka, Surathkal.

Assistant Professor in Physics, 2013-2024, National Institute of Technology Karnataka , Surathkal.

Postdoctoral Researcher, 2012-2013, University of Groningen, The Netherlands. 

Research Assistant (RA), 2008 -2012, University of Cincinnati, Ohio, USA. 

CSIR Junior Research Fellow, 2007-2008, Indian Institute of Technology Delhi, India. 

Project grant award from Vision Group of Science and Technology (VGST), Government of Karnataka, India. Project duration: 2019-2022. 

Extramural (EMR) project grant award from Science and Engineering Research Board (SERB), Department of Science and Technology, Govt of India. Project duration: 2017-2020. 

Post doctoral fellowship (2012) by FOM Netherlands to work at University of Groningen, The Netherlands; Project advisor: Prof. Bart J. van Wees. 

Best poster award at the 56th Annual Conference on Magnetism and Magnetic Materials at Scottsdale, AZ, USA in 2011. 

Travel grant to attend 56th Annual Conference on Magnetism and Magnetic Materials at Scottsdale, AZ, USA in 2011; awarded by University of Cincinnati, Ohio, USA. 

Engineering Research Cleanroom Award (University of Cincinnati) in 2008 (Cash award USD 1500). 

Teaching and Research Assistantship during PhD (2008-2012) at the University of Cincinnati, Ohio, USA. 

Qualified for Lecturership (LS) and Junior Research Fellowship (JRF) in National Eligibility Test, jointly conducted by University Grants Commission and Council of Scientific and Industrial Research (UGC–CSIR), India in 2006. 

First Class 3rd position with Distinction marks at BSc (Physics Honors) from Gauhati University in 2003.