Faculty Details


Basudev Roy

Associate Professor

HSB 271

Ph.D. IISER Kolkata

Areas of Interest

  • Experimental soft matter physics
  • high resolution imaging and optical tweezers

Current Research

We are an upcoming group in the Physics department of IIT Madras with primary emphasis on Optical Tweezers based study of statistical mechanics and biological systems. We are essentially going to divide our time for two topics, namely, High Resolution Imaging based systems and Optical Tweezers based systems. We would like to couple high resolution imaging systems to optical tweezers to study biological systems. Optical Tweezers are a tightly focused beam of light which generates a three dimensional potential well for trapping microparticles. These can not only be used to apply and detect controlled forces but also controlled torques upon using birefringent microparticles. We would like to couple single cells to the optical tweezers, to probe both inside the cell and on the membrane. We would also like to enhance optical tweezers intrumentation to sense forces on cells passively without actually applying a force directly.


Current PhD Students

  • PH17D048    URVASHI NAKUL (Co-Guidance)
  • PH20D039    GOKUL N P
  • PH20D087    SRESTHA ROY

Recent Publications

  • Realisation of pitch-rotational torque wrench in two-beam optical tweezers. Muruga Lokesh, Rahul Vaippully, Vidya P. Bhallamudi, Anil Prabhakar and Basudev Roy. Journal of Physics Communications. 5. 115015. 2021.
  • Estimation of rolling work of adhesion at the nanoscale with soft probing using optical tweezers. Muruga Lokesh, Rahul Vaippully, Gokul N, Srestha Roy, Vidya P. Bhallamudi, Anil Prabhakar and Basudev Roy. RSC Advances. 11. 34636. 2021.
  • Calcium-channel blockers exhibit divergent regulation of cancer extravasation through the mechanical properties of cancer cells and underlying vascular endothelial cells. Vaibavi Ramanujam, Manoj S., Rahul Vaippully, Privita Edwina, Basudev Roy and Saumendra Bajpai. Cell Biophysics and Biochemistry. 2021.
  • Estimation of motional parameters using emission from upconverting nanoparticles optically trapped at the absorption resonance. Kumar, Amrendra; Gunaseelan, M.; Vaidya, Gaurav; Vaippully, Rahul; Roy, Basudev. European Physical Journal Special Topics. 2021.
  • Continuous rotational motion in birefringent particles using two near-orthogonally polarized optical tweezers beams at different wavelengths with low ellipticity. Rahul Vaippully, Muruga Lokesh and Basudev Roy. Journal of Optics. 23. 094001. 2021.
  • Continuous rotational motion in birefringent particles using two near-orthogonally polarized optical tweezers beams at different wavelengths with low ellipticity. Vaippully, Rahul; Lokesh, Muruga; Roy, Basudev. Journal of Optics (UK). 2021.
  • Breaking the diffraction limit in absorption spectroscopy using upconverting nanoparticles. Kumar, Sumeet; Gunaseelan, M.; Vaippully, Rahul; Banerjee, Ayan; Roy, Basudev. Nanoscale. 2021.
  • Detection of sub-degree angular fluctuations of the local cell membrane slope using optical tweezers. Vaippully, Rahul; Ramanujan, Vaibavi; Gopalakrishnan, Manoj; Bajpayee, Saumendra; Roy, Basudev. Soft Matter. 2020.
  • Measurement of viscoelastic properties of the cellular cytoplasm using optically trapped Brownian probes. Vaippully, Rahul; Ramanujam, Vaibavi; Bajpai, Saumendra; Roy, Basudev. Journal of Physics Condensed Matter. 2020.
  • Pitch-rotational manipulation of single cells and particles using single-beam thermo-optical tweezers. Sumeet Kumar, M. Gunaseelan, Rahul Vaippully, Amrendra Kumar, Gaurav Vaidya, S. Dutta, Basudev Roy. Biomedical Optics Express. 2020.
  • Trapped in out-of-equilibrium stationary state: Hot Brownian motion in optically trapped upconverting nanoparticles. Sumeet Kumar, A. Kumar, Gunaseelan M., R. Vaippully, D. Chakraborty, J. Senthilselvan and Basudev Roy. Frontiers in Physics. 2020.
  • Study of adhesivity of surfaces using rotational optical tweezers. Rahul Vaippully, Dhanush Bhatt, Anand Dev Ranjan and Basudev Roy. Physica Scripta. 2019.
  • Self-assembly and complex manipulation of colloidal mesoscopic particles by active thermocapillary stress. Ghosh, Subhrokoli; Biswas, Aritra; Roy, Basudev; Banerjee, Ayan. Soft Matter. 2019.
  • Detection of self-generated nanowaves on the interface of an evaporating sessile water droplet. Bhatt, D.; Vaippully, R.; Kharbanda, B.; Ranjan, A.; Dharod, V.; Satapathy, D.; Roy, B.. Optics express. 2019.
  • Free and confined Brownian motion in viscoelastic Stokes-Oldroyd B fluids. Shuvojit Paul, Basudev Roy, Ayan Banerjee. Journal of Physics: Condensed matter. 2018.
  • Phragmoplast Orienting Kinesin 2 is a weak motor switching between processive and diffusive modes. Mayank Chugh, Maja Reissner, Michael Bugiel, Elisabeth Lipka, Arvid Herrmann, Basudev Roy, Sabine Mueller, Erik Schaffer. Biophysical Journal. 2018.
  • Determination of pitch rotation in a spherical birefringent microparticle. Basudev Roy*, Avin Ramaiya, Erik Schaffer. Journal of Optics. 2018.
  • Kinesin rotates unidirectionally and generates torque while walking on microtubules. Avin Ramaiya*, Basudev Roy*, Michael Bugiel and Erik Schaffer. Proceedings of National Academy of Sciences (USA). 2017.
  • Direct verification of the fluctuation-dissipation relation in viscously coupled oscillators. Shuvojit Paul, Abhrajit Laskar, Rajesh Singh, Basudev Roy, Ronojoy Adhikari, Ayan Banerjee. Physical Review E (Rapid Communications). 2017.
  • Using Brownian motion to measure shape asymmetry in mesoscopic matter using optical tweezers. Basudev Roy, Argha Mondal, Sudipta Bera, Ayan Banerjee. Soft Matter. 12. 5077. 2016.
  • Site specific supramolecular heterogeneous catalysis by optically patterned soft oxometalate– porous organic framework (SOM–POF) hybrid on a chip. Preethi Thomas, Pei Cuiying, Basudev Roy, Subhrokoli Ghosh, Santu Das, Ayan Banerjee, Teng Ben, Shilun Qiu, Soumyajit Roy. Journal of Materials Chemistry A. 2015.
  • Exploring the phase explosion point of water using SOM-mediated micro-bubbles (Invited Paper).. Basudev Roy, Mayukh Panja, Subhrokoli Ghosh, Supratim Sengupta, Dibyendu Nandy, Ayan Banerjee. New Journal of Chemistry. 2015.
  • Simultaneous detection of rotational and translational motion in optical tweezers by measurement of backscattered intensity. Basudev Roy, Bera Sudipta K., Ayan Banerjee. Optics Letters. 2014.
  • Enhanced richness of notes by modulation of boundary conditions in a stringed musical instrument. Basudev Roy. Current Science. 2014.
  • Self-Assembly of Mesoscopic Materials To Form Controlled and Continuous Patterns by Thermo-Optically Manipulated Laser Induced Microbubbles. Basudev Roy, Manish Arya, Preethi Thomas, Julius Konstantin Jurgschat, K. Venkata Rao, Ayan Banerjee, Chilla Malla Reddy, Soumyajit Roy. Langmuir. 2013.


  • 2017 :  (Jul - Nov) - EP2100-Introduction to Engineering Optics
  • 2018 :  (Jan-May) - PH1020 Physics II; (Jul - Nov) - PH1010 Physics I
  • 2019 :  (Jan-May) - PH2070 Introduction to Biological Physics; (Jul - Nov) - EP2100 Introduction to Engineering Optics/ PH5060 Physics Lab I (PG)
  • 2020 :  (Jan-May) - EP3291 Engineering Physics Lab IV/ PH2070 Introduction to Biological Physics; (Jul - Nov) - EP2100 Introduction to Engineering Optics/ PH5060 Physics Lab I (PG)
  • 2021 :  (Jan-May) - PH1020 Physics II; (Jul - Nov) - PH1010 Physics I
  • 2022 :  (Jan-May) - PH1030 Physics Laboratory I / PH2070 Introduction to Biological Physics ; (Jul - Nov) - PH1010 Physics I
  • 2023 :  (Jan-May) - PH1030 Physics Laboratory I / PH2080 Physics Lab IV