Research

My recent work seems to be mostly around exploring elementary phenomena, often through analogies, using solid state systems. Some of the themes have been:
  • Obserable effects of zero-point motion of atoms [electric field of zero-point phonons, bandgap renormalization due to zero-pt motion of atoms]
  • First-order phase transitions [Metastable phases, hysteresis, kinetic spinodals]
  • Coherence and diffraction
  • Hydrogen atom (astro-)physics with excitons [Pressure (Kothari) and thermal (Saha) ionization, effect of perturbing electric and magnetic fields..]

The experimental techniques we use include low temperature transport (resistance, magnetoresistance, Hall, resistance noise), thermal analysis (latent heat), and optical spectroscopy (photoluminescence, magneto-photoluminescence, absorption, time-resolved excitation-correlation PL..). We also have a homemade pulsed magnet [35 tesla!] to assist in spectroscopy and transport studies. My colleague Bipul Pal and I share the spectroscopy laboratory and have been closely cooperating on many problems.

Recent Publications*

  • Kinetic spinodal instabilities in the Mott transition in V2O3: Evidence from hysteresis scaling and dissipative phase ordering, Tapas Bar, Sujeet Kumar Choudhary, Md. Arsalan Ashraf, K. S. Sujith, Sanjay Puri, Satyabrata Raj, Bhavtosh Bansal, 2018, Physical Review Letters 121, 045701 [abstract] [pdf]
  • Distinguishing quantum dot-like localized states from quantum well-like extended states across the exciton emission line in a quantum well Sumi Bhuyan, Richarj Mondal, Bipul Pal, Bhavtosh Bansal, 2018, Journal of Physics: Condensed Matter 30, 105402  [abstract] [pdf]
  • Measurements of the electric field of zero-point optical phonons in GaAs quantum wells support the Urbach rule for zero-temperature lifetime broadening, Rupak Bhattacharya, Richarj Mondal, Pradip Khatua, A. Rudra, E. Kapon, S. Malzer, G. Doehler, Bipul Pal, Bhavtosh Bansal, 2015, Physical Review Letters 114, 047402. [abstract] [pdf]  [supplementary]
  • Anti-Stokes luminescence in the light of second order perturbation theory, Rupak Bhattacharya, Bipul Pal, Bhavtosh Bansal, 2014, Applied Physics Letters 105, 191102 [pdf] [journal]
  • Anomalous effects of ultradilute impurities on heat diffusion in liquids, Deepak K. Ambast, Richarj Mondal, B. Pati, S. S. Zade, Bhavtosh Bansal, Bipul Pal, 2015, Optics Communication 334, 184 [pdf] [journal]
  • Optical density of states in ultradilute GaAsN alloy: Coexistence of free excitons and impurity band of localized and delocalized states, Sumi Bhuyan, S. Das, S. Dhar, Bipul Pal, Bhavtosh Bansal, 2014, Journal of Applied Physics 116, 023103 [pdf] [journal]
  • Khatua, Bansal, and Shahar Reply [to comment on "Single-slit electron diffraction with Aharonov-Bohm phase:..."], Pradip Khatua, Bhavtosh Bansal, Dan Shahar, 2014, Physical Review Letters 113, 158902
  • [Comment]  [journal] [pdf]
  • Light emission despite doubly-forbidden radiative transitions in AlP/GaP quantum wells: Role of localized states, Sumi Bhuyan, Richarj Mondal,  Pradip Khatua, M. Semtsiv, W. T. Masselink, J. Leotin, Bipul Pal, Bhavtosh Bansal, 2013, Journal of Applied Physics 114, 163101 [pdf] [journal]
  • Pauli blocking dynamics in optically excited quantum dots: A picosecond excitation-correlation spectroscopic study, Richarj Mondal, Bhavtosh Bansal, A. Mandal, S. Chakrabarti, Bipul Pal, 2013, Physical Review B 87, 115317 [pdf] [journal]
  • Scattering by charged dislocations in semiconductors, Bhavtosh Bansal,  Rituparna Ghosh, V. Venkataraman, 2013, Journal of Applied Physics 113, 163705 [pdf] [journal]
  • On conversion of luminescence into absorption and the van Roosbroeck-Shockley relation, Rupak Bhattacharya, Bipul Pal, Bhavtosh Bansal, 2012, Applied Physics Letters, 100, 222103 [pdf] [journal]
  • Charge separation and temperature-induced carrier migration in Ga1-xInxNyAs1-y multiple quantum wells, T. Nuytten, M. Hayne, B. Bansal, H.Y. Liu, M. Hopkinson, V. V. Moshchalkov, 2011, Physical Review B 84, 045302 [pdf] [journal]
     Reviews
  • Self-Assembly in semiconductor epitaxy: From growth mechanisms to device applications, Arnab Bhattacharya and Bhavtosh Bansal, Chapter 26 Handbook of Crystal Growth Vol. 3, 2nd Edition, Elsevier 2015, 1057–1099 Ed T. Kuech [abstract] [pdf]

  • High-field magneto-photoluminescence of semiconductor nanostructures, Manus Hayne, Bhavtosh Bansal, 2012, Luminescence 27, 179 [pdf] [journal]
*Colon in the title indicates that the paper is full of.... :)


Current Group
  • Tapas Bar (PhD)
  • Kingshuk Mukhuti (PhD)
  • Basabendra Roy (PhD)
  • Satyaki Kundu (PhD)
  • Umesh Chandra Sahu (MS thesis)

Alumni: Richarj Mondal (PhD 2015), Sumi Bhuyan (PhD 2017), Rupak Bhattacharya (PhD 2017), Md Arsalan Ashraf (MS 2014), Sujeet K. Choudhary (MS 2015), Sujith K. S. (MS 2015), Anees A. A. (MS 2016), Ajmal Kareem (MS 2016), Kiran Kumar S. (MS 2016), Anjana K. (MS 2017), Kamal Raj R. (MS 2017), Mithun S.Prasad (MS 2017), Shruti J. S. (MS 2018)

Teaching

....an instrument wielded by professors to manufacture professors, who, when their turn comes, will manufacture professors.
-Simone Weil (Need for Roots)


Lecture Courses
Laboratory Courses
  • First year Physics Laboratory (Autumn 2018, Autumn 2017, Autumn 2014, Spring 2014)
  • Condensed Matter Laboratory (Autumn 2016, 2015)
  • Advanced Experimental Laboratory (Spring 2014)
  • Waves and Optics Lab (2nd Yr) [Spring 2011, 2012]

      

       
       Bhavtosh Bansal

       Associate Professor,
       Department of Physical Sciences,
       Indian Institute of Science Education and Research Kolkata,
       Nadia 741246, West Bengal, INDIA.
      
        Email: bhavtosh iiserkol ac in
        Phone: +91 (0)33 66340000 ext. 1289
    
 
       [Note: Currently there are no PhD or Project openings.]
   

Updated: June 2018