About

I was born and raised in the southern Indian coastal city named Chennai (fondly called Madras). I am currently a postdoctoral research associate with Prof. Bane Vasic at the University of Arizona, Tucson, AZ, USA. I completed my doctoral studies in the Department of Electrical and Computer Engineering at Duke University, Durham, NC, USA, under the supervision of Prof. Henry Pfister and
Prof. Robert Calderbank at the Rhodes Information Initiative at Duke (iiD). My dissertation is here.

Prior to this, I completed my Master of Science (M. S.) degree at Texas A&M University, where I worked with Prof. Henry Pfister on the construction of Cyclic Polar Codes. I was a graduate research intern during the summer of 2015 at Alcatel-Lucent Bell Labs, Stuttgart, Germany, where I worked on the analysis of Spatially-Coupled LDPC ensembles over burst erasure channels, under the supervision of Dr. Laurent Schmalen and Dr. Vahid Aref. My Master’s thesis discusses cyclic polar codes as well as my internship work. Earlier, I completed my Bachelor of Technology (B. Tech.) degree in Electronics and Communication Engineering at Amrita University, Coimbatore, India.

My research interests are in the realms of information and coding theory (both classical and quantum), compressed sensing, and general inference problems. Currently, I am working on the construction of quantum codes and synthesis of their fault-tolerant logical operators for quantum computing. I am also interested in codes and decoding algorithms for quantum communications. I am a Member of the IEEE and the Information Theory Society.

I love pencil sketching and like to read about science, philosophy and life. I play cricket, volleyball and bowling. I am a novice writer and hope to disseminate productive thought and knowledge through this powerful platform called internet. My old blog is here.

This website is powered by Jekyll and this theme is an open source contribution by Panos Sakkos. All suggestions for improving this website are most welcome.

Updates

Nov. 2020: A double blow to the arXiv on the same day! One paper on mitigating coherent noise passively using stabilizer codes, another on approximate unitary 3-designs from transvection Markov chains and Kerdock codes

Sep. 2020: I joined Prof. Bane Vasic’s lab at University of Arizona as a postdoctoral research associate!

July 2020: Our paper connecting robust quantum metrology and classical weight distributions is posted on arXiv

June 2020: Our paper on unraveling the Clifford hierarchy using Weyl expansions is posted on arXiv

May 10, 2020: I have been officially conferred the Doctor of Philosophy (Ph.D.) degree!

March 18, 2020: I successfully defended my Ph.D. in Electrical Engineering at Duke! My dissertation is called Classical Coding Approaches to Quantum Applications and my defense talk is on YouTube!

I turned out to be the first ever student in Duke Engineering to give the Ph.D. defense fully online

March 2020: Our paper on a quantum message passing (BPQM) receiver for free-space laser communications is posted on arXiv. We think this points to a new and exciting application for a small, special-purpose, photonic quantum computer!

Feb. 2020: I gave a graduation day talk and poster in the 2020 Information Theory and Applications (ITA) workshop about our work on a belief-propagation with quantum messages (BPQM) algorithm

Jan. 2020: I gave a talk in Quantum Information Processing (QIP ‘20) about our transversal T work! The video is available online

Our shorter paper emphasizing the new classical coding open problem from quantum T gates is now posted on arXiv

Timeline

Publications

A list of my publications is below. You can also follow me on Google Scholar and ResearchGate (which includes unpublished notes and research).

Here is my most recent Curriculum Vitae.

Journal Articles and Preprints

  1. N. Tan, N. Rengaswamy, and R. Calderbank, “Approximate unitary 3-designs from transvection Markov chains,” arXiv preprint arXiv:2011.00128, Nov. 2020 [Online]. Available at: https://arxiv.org/abs/2011.00128

  2. J. Hu, Q. Liang, N. Rengaswamy, and R. Calderbank, “Mitigating Coherent Noise by Balancing Weight-2 Z-Stabilizers,” arXiv preprint arXiv:2011.00197, Nov. 2020 [Online]. Available at:
    https://arxiv.org/abs/2011.00197


  3. Y. Ouyang and N. Rengaswamy, “Weight Distribution of Classical Codes Influences Robust Quantum Metrology,” arXiv preprint arXiv:2007.02859, Jul. 2020 [Online]. Available at:
    http://arxiv.org/abs/2007.02859


  4. T. Pllaha, N. Rengaswamy, O. Tirkkonen, and R. Calderbank, “Un-Weyl-ing the Clifford Hierarchy,” arXiv preprint arXiv:2006.14040, Jun. 2020 [Online]. Available at: http://arxiv.org/abs/2006.14040

  5. N. Rengaswamy, K. P. Seshadreesan, S. Guha, and H. D. Pfister, “Belief Propagation with Quantum Messages for Quantum-Enhanced Classical Communications,” accepted to npj Quantum Information, Mar. 2020 [Online]. Available at: http://arxiv.org/abs/2003.04356

  6. T. Can, N. Rengaswamy, R. Calderbank, and H. D. Pfister, “Kerdock Codes Determine Unitary 2-Designs,” IEEE Trans. Inform. Theory, vol. 66, no. 10, pp. 6104–6120, 2020 [Online]. Available at:
    http://arxiv.org/abs/1904.07842


  7. N. Rengaswamy, R. Calderbank, M. Newman, and H. D. Pfister, “On Optimality of CSS Codes for Transversal T,” IEEE J. Sel. Areas in Inf. Theory, vol. 1, no. 2, pp. 499–514, 2020 [Online]. Available at: http://arxiv.org/abs/1910.09333

  8. N. Rengaswamy, R. Calderbank, S. Kadhe, and H. D. Pfister, “Logical Clifford Synthesis for Stabilizer Codes,” IEEE Trans. Quantum Engg., vol. 1, 2020 [Online]. Available at: http://arxiv.org/abs/1907.00310

  9. S. Brandsen, M. Lian, K. D. Stubbs, N. Rengaswamy, and H. D. Pfister, “Adaptive Procedures for Discrimination Between Arbitrary Tensor-Product Quantum States,” arXiv preprint arXiv:1912.05087, Dec. 2019 [Online]. Available at: http://arxiv.org/abs/1912.05087

  10. N. Rengaswamy, R. Calderbank, and H. D. Pfister, “Unifying the Clifford Hierarchy via Symmetric Matrices over Rings,” Phys. Rev. A, vol. 100, no. 2, p. 022304, 2019 [Online]. Available at:
    http://arxiv.org/abs/1902.04022 (or) https://journals.aps.org/pra/abstract/10.1103/PhysRevA.100.022304


  11. V. Aref, N. Rengaswamy, and L. Schmalen, “Finite-Length Analysis of Spatially-Coupled Regular LDPC Ensembles on Burst-Erasure Channels,” IEEE Trans. Inform. Theory, vol. 64, no. 5, pp. 3431–3449, 2018 [Online]. Available at: http://arxiv.org/abs/1611.08267 (or) http://ieeexplore.ieee.org/document/8272426/

  12. N. Rengaswamy, R. Calderbank, S. Kadhe, and H. D. Pfister, “Synthesis of Logical Clifford Operators via Symplectic Geometry,” arXiv preprint arXiv:1803.06987, 2018 [Online]. Available at:
    http://arxiv.org/abs/1803.06987


Conference Articles

  1. N. Rengaswamy, K. P. Seshadreesan, S. Guha, and H. D. Pfister, “Quantum Advantage via Qubit Belief Propagation,” in Proc. IEEE Int. Symp. Inform. Theory, 2020, pp. 1824–1829. Slides

  2. N. Rengaswamy, R. Calderbank, M. Newman, and H. D. Pfister, “Classical Coding Problem from Transversal T Gates,” in Proc. IEEE Int. Symp. Inform. Theory, 2020, pp. 1891–1896 [Online]. Available at:
    http://arxiv.org/abs/2001.04887
    Slides

  3. T. Can, N. Rengaswamy, R. Calderbank, and H. D. Pfister, “Kerdock Codes Determine Unitary 2-Designs,” in Proc. IEEE Int. Symp. Inform. Theory, 2019, pp. 2908–2912. Slides

  4. N. Rengaswamy, R. Calderbank, S. Kadhe, and H. D. Pfister, “Synthesis of Logical Clifford Operators via Symplectic Geometry,” in Proc. IEEE Int. Symp. Inform. Theory, 2018, pp. 791–795. Slides

  5. N. Rengaswamy, L. Schmalen, and V. Aref, “On the Burst Erasure Correctability of Spatially Coupled LDPC Ensembles,” in Proc. IEEE Intl. Zurich Seminar on Commun., 2016, pp. 155–159.

  6. V. Aref, N. Rengaswamy, and L. Schmalen, “Spatially Coupled LDPC Codes Affected by a Single Random Burst of Erasures,” in Proc. Int. Symp. on Turbo Codes & Iterative Inform. Proc., 2016, pp. 166–170.

  7. N. Rengaswamy and H. D. Pfister, “Cyclic Polar Codes,” in Proc. IEEE Int. Symp. Inform. Theory, 2015, pp. 1287–1291. Slides

Theses

  1. N. Rengaswamy, “Classical Coding Approaches to Quantum Applications,” PhD thesis, Duke University, 2020 [Online]. Available at: http://arxiv.org/abs/2004.06834 Slides

  2. N. Rengaswamy, “On Cyclic Polar Codes and the Burst Erasure Performance of Spatially-Coupled LDPC Codes,” Master's thesis, Texas A&M University, 2015
    [Online]. Available at: http://arxiv.org/abs/2004.06875
    Slides

Contact

Drop me an email if you are interested in my work or want to collaborate or to even say hello!