Faculty Details

Areas of Interest

• Classical and quantum dynamical systems
• Nonlinear dynamics and chaos
• Chaos in gauge theories
• Quantum information theory

Current Research

Current Research Interests are  Dynamical Systems Theory, Quantum Dynamics, Quantum Optics, and QuantumI Information and Computation.Optical tomograms  and qubit tomograms are used to directly identify nonclassical effects such as squeezing and  higher-order squeezing  of quantum states and quantum entanglement  between subsystem states as the full system evolves under a Hamiltonian.  This program circumvents elaborate state reconstruction. Research in the interface of Dynamical Systems and Quantum Dynamics  involves tracking the ergodicity properties of quantum observables using tools from Classical Dynamical Systems theory. The various focus areas in the group are state reconstruction, classical and quantum entanglement, wavepacket revival phenomena in quantum systems, open quantum systems and decoherence,  The IBM quantum computing platform is used to examine nonclassical properties of optical states and spin systems by employing appropriate equivalent circuits.

Students

Current PhD Students

• PH18D043    SOUMYABRATA PAUL
• PH20D018    SREELEKSHMI PILLAI (Co-Guidance)

Recent Publications

• Tomographic entanglement indicators from NMR experiments. B Sharmila, VR Krithika, S Pal, TS Mahesh, S Lakshmibala. arXiv:2105.08555.
  DOI: https://doi.org/10.48550/arXiv.2105.08555. https://arxiv.org/pdf/2105.08555.pdf 2021.
• Exact eigenvalue order statistics for the reduced density matrix of a bipartite system. B Sharmila, V Balakrishnan, S Lakshmibala. arXiv:2110.01022.
  DOI: https://doi.org/10.48550/arXiv.2110.01022. https://arxiv.org/pdf/2110.01022.pdf 2021.
• Tomographic entanglement indicators in frequency combs and Talbot carpets. B Sharmila, S Lakshmibala, V Balakrishnan. arXiv:2111.14002.
  DOI: https://doi.org/10.48550/arXiv.2111.14002. https://arxiv.org/pdf/2110.01022.pdf 2021.
• Manifestations of changes in entanglement and onset of synchronization in tomograms. S Paul, S Lakshmibala, V Balakrishnan, S Ramanan. arXiv:2112.13262.
  DOI: https://doi.org/10.48550/arXiv.2112.13262. https://arxiv.org/pdf/2112.13262.pdf 2021.
• The central force problem in n dimensions. V. Balakrishnan, Suresh Govindarajan and S. Lakshmibala. Resonance. 25. 513-538. 2020.
• Tomographic entanglement indicators in multipartite systems. B. Sharmila, S. Lakshmibala and V. Balakrishnan. Q. Infor. Process.. 19. 127 (1-12). 2020.
• Bifurcations, time-series analysis of observables, and network properties in a tripartite quantum system. Pradip Laha, S. Lakshmibala and V. Balakrishnan. Letters A. 384. 126565 (1-10) . 2020.
• Time-series and network analysis in quantum dynamics: Comparison with classical dynamics. Pradip Laha, S. Lakshmibala and V. Balakrishnan. Int. J. Theor. Phys.. 59. 3476-3490. 2020.
• Signatures of avoided energy- level crossings in entanglement indicators obtained from quantum tomograms. B. Sharmila, S. Lakshmibala and V. Balakrishnan. J. Phys. B: At. Mol. Opt. Phys.. 53. 245502(1-9). 2020.
• Recurrence Network Analysisin a Model Tripartite Quantum System . Pradip laha, Lakshmibala S, Balakrishnan V. EPL . 125 .
  DOI: 10.1209/0295-5075/125/60005. 2019.
• Nonclassical effects in Optomechanics: Dynamics and Collapse of Entanglement . Pradip Laha, Lakshmibala S, Balakrishnan V. JOSA B. 36. 575 .
  DOI: 10.1364/JOSAB.36.000575. 2019.
• Estimation of Nonclassical Properties of Multiphoton Coherent States from Optical Tomograms . Pradip Laha, Lakshmibala S, Balakrishnan V . J. Mod. Opt. .
  DOI: 10.1080/09500340.2018.1454527. 2018.
• Signatures of Nonclassical Effects in Optical Tomograms . Sharmila B, Saumitran K, Lakshmibala S, Balakrishnan V. J.Phys.B: At. Mol. Opt. Phys.. 50 (4) . 045501. 2017.
• Entanglement Dynamics in a Model Tripartite Quantum System . Pradip Laha, Sudarsan B, S.Lakshmibala, V. Balakrishnan. Int. J. Theor. Phys..
  DOI: 10.1007/s10773-016-3033-8. 2016.
• Dynamics of an open quantum system interacting with a quantum environment . Shankar A, Lakshmibala S, Balakrishnan V. J.Phys. B. 47. 215505. 2014.
• Ehrenfest's Theorem and Nonclassical States of Light . Lijo T. George, C. Sudheesh, S. Lakshmibala and V. Balakrishnan. Ehrenfest's Theorem in Quantum Mechanics, Resonance, January 2012.. 2012.
• Ehrenfest's Theorem and Nonclassical States of Light . Lijo T. George, C. Sudheesh, S. Lakshmibala, and V. Balakrishnan. Dynamics of Nonclassical States of Light, Resonance, February 2012.. 2012.
• Recurrence statistics of observables in quantum-mechanical wave packet dynamics. . C. Sudheesh, S. Lakshmibala and V. Balakrishnan . Europhys. Lett. 90, (50001), 1-6 (2010).. 2010.
• Dynamics of quantum observables in entangled states. . C. Sudheesh, S. Lakshmibala and V. Balakrishnan. Phys. Lett. A. 373. 2814-2819. 2009.
• Ergodicity properties of quantum expectation values in entangled states . C. Sudheesh, S. Lakshmibala and V. Balakrishnan. In Proceedings of the National Conference on Nonlinear Systems and Dynamics 2006,. 2006.
• Wave packet dynamics of photon-added coherent states . C.Sudeesh, S. Lakshmibala and V. Balakrishnan. J. Phys. B. At. Mol. Opt. Phys.. 39. 3345-3359. 2006.
• Wave packet dynamics of entangled two-mode states. . C. Sudheesh, S. Lakshmibala and V. Balakrishnan. Eds. M. Lakshmanan and R. Sahadevan (Allied Publishers, Chennai, India, Jan 2006).. 2006.
• Squeezing and higher-order squeezing of photon-added coherent states propagating in a Kerr-like medium . C. Sudheesh, S. Lakshmibala and V. Balakrishnan. New Jour. of Physics Vol. . 7. Issue 11, 1. 2005.
• On the connection between biased dichotomous diffusion and the one-dimensional Dirac equation . V. Balakrishnan and S. Lakshmibala,. Europhys. Letts. Vol.. 71 (5). 744-750. 2005.
• Phase estimation, photon cloning and the Bernoulli map . S. Lakshmibala and M.V. Satyanarayana . Resonance. 9. 46-56. 2004.
• Principle. . S. Lakshmibala. Phys. Lett. A Vol.. 329. 14-21. 2004.
• Manifestations of wave packet revivals in the moments of observables . C. Sudheesh, S. Lakshmibala and V. Balakrishnan. J.Opt.B Quantum Semiclass. Opt.7, S728-S735 (2004).. 2004.

Teaching

• 2017 :  (Jan - May) - PH5170 Quantum Mechanics II; (Jul - Nov) - EP2210 Principles of Quantum Mechanics
• 2018 :  (Jan - May) - PH5170 Quantum Mechanics II; (Jul - Nov) - PH5100 Quantum Mechanics- I
• 2019 :  (Jan - May) - PH1030 Physics Laboratory I / PH1040 Physics Laboratory II / PH5170 Quantum Mechanics II
• 2020 :  (Jan - May) - PH5620 Coherent and Quantum Optics; (Jul - Nov) - ID5791 Project II / PH1010 Physics I
• 2021 :  (Jan - May) - PH1030 Physics Laboratory I / PH5620 Coherent and Quantum Optics ; (Jul - Nov) - EP2110 Introduction to Mathematical Physics / PH1030 Physics Laboratory I
• 2022 :  (Jan - May) - PH1030 Physics Laboratory I / PH5620 Coherent and Quantum Optics ; (Jul - Nov) - PH1030 Physics Laboratory I / PH7080 Foundations in Theoretical Physics
• 2023 :  (Jan - May) - EP3190 Engineering Physics Lab II / PH7080 Foundations in Theoretical Physics