Welcome to my homepage!
I am Dr. Chinmay C. Khandekar. You will find here a compilation of my current and previous research works with collaborators, and other useful resources. Broadly speaking, our research work focusses on understanding fundamental properties of light (photons) and harnessing them for practical applications related to solar cells and renewable technologies, imaging, material characterization, metrology, display technologies, light sources, micro/nanoscale heat management etc.
Education: PhD from Princeton University, USA.
Bachelors from IIT Bombay, India.
Solid-state thermal refrigeration technology based on light and nonlinear materials
Nonlinear Optics to beat the fundamental blackbody limit imposed by Kirchhoff's law
New Kirchhoff's laws
for nonreciprocal media
Thermal memory to store information as temperature
Nonlinear optics for controlling radiative heat
Thermal radiation from the sun at temperature T~6000K peaks at frequencies above the photovoltaic cell's bandgap (around 1eV or 1micron in wavelength) and is converted into electricity. Thermal radiation from hot bodies on earth at temperatures T~300 to 600K, peaks at mid-infrared wavelength (larger than 3micron in wavelength). It cannot be readily converted to electricity because it carries photons of energy below the bandgap. To directly harness this abundant below-bandgap thermal radiation with a PV cell, we explore the possibility of using nonlinear optics for passively upconverting (in frequency) mid-infrared thermal radiation to near-infrared wavelengths. For instance, two mid-infrared thermal photons can combine to form a single near-infrared photon in a suitably engineered nonlinear resonant photonic system.
Apart from the practical relevance, this problem is fundamentally important because nearly all thermal radiation phenomena have been analyzed so far within the linear response theory. When we go beyond the linear regime, it is challenging to ensure that the fundamental thermodynamic laws are not violated due to nonlinear mixing of photons of different average thermal energies. We carefully address this issue and based on a thermodynamically consistent theory, we prove that we can indeed upconvert and enhance thermal radiation by using engineered nonlinear photonic systems. We also show that thermal radiation of nontrivial statistics and multi-photon intensity correlations can be generated by simply heating properly designed nonlinear nanophotonic systems.
Read more: Opt. Exp. 2020 (Editor's Pick),
I completed my BTech in Engineering Physics at IIT Bombay, India (link). At that time, I was interested in both condensed matter physics and photonics. After graduation in 2013, I joined computational nanophotonics group of Alejandro Rodriguez at Princeton University (link). We worked on many theory problems. Amongst them, our work on 'nonlinear optics for heat control' stands out as a major contribution according to me.
After completing my PhD at Princeton in 2018, I joined Zubin Jacob's group at Purdue University (link) as a Lillian Gilbreth Postdoctoral Fellow. We worked on many interesting topics and also experiments. I believe that our work related to 'spin of thermal radiation' stands out as a major contribution during this time.
Recently, I joined Shanhui Fan's group at Stanford University (link). As a specialist in the field of nanophotonics, I am quite fortunate to be guided by these mentors who are leaders in this field. I also got a chance to learn many tricks and techniques in this field from very bright colleauges, collaborators, and peers at various universities. I am quite open-minded about new collaborations. If you are interested to know more or work together, please don't hesitate to contact me.