Publications

Feedback trap based on optical tweezers

Mpemba effect

Bechhoefer, J., Kumar, A., & Chétrite, R. (2021). A fresh understanding of the Mpemba effect. Nature Reviews Physics.
Kumar, A., Chetrite, R., & Bechhoefer, J. (2021). Anomalous heating in a colloidal system. arXiv preprint arXiv:2104.12899.
Chétrite, R., Kumar, A., & Bechhoefer, J. (2021). The metastable Mpemba effect corresponds to a non-monotonic temperature dependence of extractable work. Frontiers in Physics, 9, 141.
Kumar, A., & Bechhoefer, J. (2020). Exponentially faster cooling in a colloidal system. Nature, 584, 64-68.

Scheme for constructing a feedback trap

Kumar, A., & Bechhoefer, J. (2019). Shaping arbitrary energy landscapes with feedback. Physics in Canada, 75.
Kumar, A., & Bechhoefer, J. (2018). Nanoscale virtual potentials using optical tweezers. Applied Physics Letters, 113, 183702.
Kumar, A., & Bechhoefer, J. (2018, September). Optical feedback tweezers. In Optical Trapping and Optical Micromanipulation XV (Vol. 10723, p. 107232J). International Society for Optics and Photonics.

Trapped bead in air using photophoretic forces

Sil, S., Saha, T. K., Kumar, A., Bera, S. K., & Banerjee, A. (2017). Dual-mode optical fiber-based tweezers for robust trapping and manipulation of absorbing particles in air. Journal of Optics, 19, 12LT02.
Bera, S. K., Kumar, A., Sil, S., Saha, T. K., Saha, T., & Banerjee, A. (2016). Simultaneous measurement of mass and rotation of trapped absorbing particles in air. Optics Letters, 41, 4356-4359.

You can read comments and short views about our works at

Elizaveta Dubrovina (2020). Hot and Cold. Nature Physics, 16, 898.
Noriaki Horiuchi (2018). Virtual potential. Nature Photonics, 12, 719.
Drew DeJarnette (2018). Feedback control in optical tweezers enables thermodynamic experiments for biological molecules. AIP Scilight.

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