Welcome
Thanks for visiting the Caldwell Nanophotonic Materials and Devices website.
Find out more about our team, research, publications and how to join us.
Take Virtual Tour of the Lab!
Highlights and Latest News
Caldwell group members presenting posters at VINSE 25th Annual NanoDay!
Nov. 13, 2025—10 members of the Caldwell lab presented posters at the at 25th Annual VINSE NanoDay!
Check out Ryan Kowalski’s publication “Ultraconfined terahertz phonon polaritons in hafnium dichalcogenides”
Sep. 30, 2025—Ryan Kowalski’s recently published paper in Nature Materials “Ultraconfined terahertz phonon polaritons in hafnium dichalcogenides.” https://www.nature.com/articles/s41563-025-02345-0
2025 Caldwell lab group
Sep. 3, 2025— Front Row: Professor Josh Caldwell, Emmanuel Dabuo, Xiaomeng Zhang, Youngji Kim, Maddy Adams Second Row: Thiago Arnaud, Jongha Choi, Emma Bartelsen, Courtney Ragle Third Row: Ke-Sean Peter, Tony Peng, Trey Long, Ryan Kowalski, Richarda Niemann, Jeb Buchner, Maximilian Obst
Congrats to Adriana! Best Poster Award at VINSE 14th Annual Undergraduate Research Symposium
Aug. 1, 2025—Adriana LaVopa, REU student with Caldwell Lab, won the best poster award at the VINSE 14th Annual Undergraduate Research Symposium. “Local Control of Ferroelectric Switching for Optical Modulation in Al1-xBxN” In the pursuit of space- and energy-efficient devices, nanophotonics offers an avenue towards controlling opto-electronic and optical signals far below the length scales of diffraction-limited...
VINSE 14th Annual Undergraduate Research Symposium – Madeleine Adams and Adriana LaVopa
Aug. 1, 2025—Madeleine and Adriana presented their posters during the VINSE 14th Annual Undergraduate Research Symposium. Both participants did an amazing job and special thanks to Jeb Buchner and Youngji Kim for working with both. Madeline Adams is an undergraduate mechanical engineering major at Vanderbilt University and is entering her junior year. She has been with the...
Congrats to Aditha Senarath!
Jul. 11, 2025—Congratulations to Aditha Senarath on his successful dissertation defense. GaN for Space and Power Electronics: Radiation Effects Study and Development of a Nano-Optical Probe for Characterization For decades, the semiconductor industry has followed Moore’s Law, predicting a doubling of chip power every two years by doubling transistor density. However, as traditional silicon-based technologies approach their...
Caldwell lab group – BNW2025 in Nashville, TN
May. 28, 2025—Members of the Caldwell lab attended the BNW (Boron Nitride Workshop) 2025 in Nashville. Josh Caldwell is one the organizers for the Boron Nitride Workshop. This series is dedicated entirely to boron nitride. Former group member Katja Diaz-Granados designed the logo for the BNW website and t-shirts. Current members Richarda Nieman and Courtney Ragle won...
Congrats to Ryan Kowalski!
Apr. 25, 2025—Congratulations to Ryan Kowalski for successfully defending his dissertation! “Infrared Light at the Nanoscale: Confinement and Spectroscopy” Conventional optical microscopy and spectroscopy are limited by the diffraction limit, which restricts spatial resolution to approximately half the free-space wavelength of light. This constraint poses a significant barrier for the nanoscale characterization of materials and quantum systems....
Caldwell Lab group – MRS 2025 Spring meeting highlights
Apr. 17, 2025—Members of the Caldwell lab attended the 2025 MRS Spring meeting. Emma Bartelsen was the recipient of the Best Poster Award for the “Emerging Material Platforms and Fundamental Approaches for Plasmonics, Nanophotonics and Metasurfaces” symposium. Emma Bartelsen was a recipient of the Best Poster Award for the symposium “Emerging Material Platforms and Fundamental Approaches for...
2024 Fall Meeting of the Materials Research Society
Dec. 10, 2024—Prof. Caldwell attended the 2024 Fall Meeting of the Materials Research Society in Boston, MA. His presentation entitled “Exploiting and Controlling Lattice Symmetry for Infrared Nanophotonics and Thermal Transport”. This covered collaborative work with Prof. Deyu Li, Prof. Patrick Hopkins, among others, while highlighting research from Dr. Guanyu Lu and Dr. Joseph Matson, former students...
VINSE 24th Annual Nanoscience & Nanotechnology Forum
Nov. 26, 2024—Caldwell group members presenting at VINSE 24th Annual Nanoscience & Nanotechnology Forum Aditha Senarath Emmanuel K. Dabuo Thiago S. Arnaud Courtney Ragle Carson E. Snow Emanuela Riglioni Katja Diaz-Granados Emma Bartelsen
2nd Alain Aspect Symposium
Nov. 26, 2024—Prof. Caldwell is attending the 2nd Alain Aspect Symposium, with a focus on addressing climate change with quantum technologies. As part of the symposium he gave a talk highlighting the advances in polaritonics gas sensing using so called Tamm polaritons, an advance in his lab that came from funding from the Office of Naval Research....
Emma Bartelsen Summer 2024 internship at U.S. Naval Research Laboratory
Aug. 28, 2024—Emma interned at the U.S. Naval Research Laboratory (NRL) through the Naval Research Enterprise Internship Program (NREIP), funded by the Office of Naval Research (ONR). Under the mentorship of Dr. Jeremy Robinson, her research involved fabricating and characterizing solution-based molybdenum disulfide (MoS₂) thin films. She developed protocols for drop-casting films with controlled thicknesses, analyzing their...
Congrats to Katja!
Aug. 13, 2024—Congratulations to Katja Diaz-Granados for successfully defending her dissertation!
David Flores wins best poster award for VINSE REU
Aug. 2, 2024—David Flores, an NSF VINSE REU student from Penn State, won best poster award at the end of the season poster award! Congrats to David! Thank you to his two exceptional mentors John Buchner and Saurabh Dixit!!! That makes 5 years in a row for the Caldwell group!!!