MSc Research

• Estimating dislocation density using X-ray diffraction peak shape analysis
  
  I estimated the dislocation density material in a material by modelling the width of the X ray diffraction (XRD) peaks of epitaxial GeSn (Germanium-Tin) layers. This approach improves upon the traditional method of estimating dislocation density by physical counting on transmission electron images of the sample. I used the kinematic X ray scattering theory to develop a fitting function for the XRD peak width and fitted the function to experimental XRD spectrum to estimate the dislocation density.
  
  Advisor: Prof Suddhasatta Mahapatra, IIT Bombay, India
  
  Papers where the work was included: www.sciencedirect.com/science/article/abs/pii/S0038109818303934
  www.sciencedirect.com/science/article/pii/S0022024817302488

• Ground state of the Heisenberg model on a Kagome lattice within the 3-coloring state subspace
  
  The nature of the ground state of the Heisenberg model on the kagome lattice is a contentious issue int he condensed matter community. I studied the ground state obtained in the constrained 3-coloring subspace in the antiferromagnetic Heisenberg model on a kagome lattice using exact diagonalization. I studied the spin structure factor in different total spin and topological subsectors to determine if the ground state is ordered or a spin liquid.
  
  Advisor: Prof Sumiran Pujari, IIT Bombay

• Data analysis for inclusive measurement of rare B meson decays in LHCb
  
  Rare b meson decays in the LHCb experiment can help probe physics beyond the standard model by comparing the branching ratios of decay products in the experiment vs the predictions of the standard model. Inclusive measurements aim to do this by including multiple decay channels at once instead of focussing on a particular decay channel of the b meson. It can be a challenge to separate the signal from the background in such inclusive measurements. I used a machine learning algorithm (Boosted Decision Trees) on the root primer software to separate signal from background in the data. I also ported the root primer C++ code into Python for easy use and superior performance.
  
  Advisor: Prof Konstantinos Petridis, University of Bristol, UK

• Characterization and transport study of 2D Antimonene flakes
  
  2D flakes of Antimonene are predicted to have novel transport and topological properties. I did my master's thesis work in the characterization of the 2D antimonene flakes and fabricating a device from them to measure transport properties. I used scanning electron microscopy, atomic force microscopy and Raman scattering techniques to identify the best antimonene flakes among the sample in order to fabricate the device.
  
  Advisor: Prof Suddhasatta Mahapatra, IIT Bombay, India

• Verification of a unification model of the Active Galactic Nuclei (AGN)
  
  The structure of the gas disk surrounding AGNs is a contentious issue. A particular unification model proposes that AGNs can be characterized as having gas either in clumps around it or as a smooth torus. As part of a 4 member team in our astrophysics course, we tried to test this model by analyzing X ray emission spectra of some known AGN sources from the NuStar satellite catalogue. We used the HEAsoft XSPEC software to analyze the data and fitted the spectra to extract a covering factor for the AGNs. We were able to identify both types of proposed AGNs in the sources we analyzed.
  
  Advisor: Prof Vikram Rentala, IIT Bombay, India