Skip to content Skip to navigation


We create new materials where photon operations can be performed at thermodynamic limits to enable next generation information and energy conversion systems.


Thermodynamic cycles enable optimized performance of nearly every energy conversion device that underpins advanced economies.

While most thermodynamic cycles rely on a classical fluid, photons can also be used to drive thermodynamic cycles. Our team of researchers at Stanford University, University of California, Berkeley, California Institute of Technology (Caltech), Harvard University and the University of Illinois Urbana-Champaign (UIUC) strives to achieve photonic operations at thermodynamic limits by controlling the flow of photons, electrons, and phonons in atomically-architected materials, enabling entirely new energy conversion systems.

Read About Us >>




Using thickness to break symmetry

June 21, 2021

Researchers report a new type of homojunction termed a “band-bending junction” whose potential landscape depends solely on the difference in thickness between the two sides of the junction.   

Read the article

Harry Atwater named Chair of Caltech's Division of Engineering and Applied Science

April 15, 2021

Congratulations to PTL Deputy Director, Harry Atwater, for being selected as the new Chair of Caltech's Division of Engineering and Applied Science!  His five-year term will begin on July 1st.    Caltech story

Scientists uncover a process that stands in the way of making quantum dots brighter

March 25, 2021

Researchers have made the first atomic-scale observations of how nanocrystals known as quantum dots lose their ligh-producing efficientcy when excited with intense light.  The results have broad implications for developing future quantum and photonics technologies where light replaces electrons in computers and fluids in refrigerators.   More information:  Read the Article    SLAC news

Paul Alivisatos named President of University of Chicago

February 26, 2021

Paul Alivisatos, UC Berkeley’s Executive Vice Chancellor and Provost and the Samsung Distinguished Professor of Nanoscience and Nanotechnology has been appointed President of the University of Chicago.  Berkeley News

New PTL EFRC Associate Director

January 1, 2021

The Center welcomes its new Associate Director, Hendrik Utzat!  Many thanks to Carrie Hofmann for serving in this role for the first two and one-half years.


BES Early Career Network

September 29, 2020

Megan Phelan is the Center's new BES Early Career Network representative!  Many thanks to Jefferson Dixon for serving in this capacity for the first two years!



Pride Month: stories from the SPIE community

June 29, 2020

Jefferson Dixon, Ph.D. student in Professor Jen Dionne's group at Stanford and a SPIE student member, shared his experience as a LGBTQ+ scientist in optics and photonics as well as within the greater STEM community.  Read Jefferson's feature in SPIE News.  Related Tweet: link



Spinning up quantum defects in 2D materials

April 24, 2020

Researchers investigated visible single photon emitting defects in hexagonal boron nitride to explore their microscopic origin and structure-function correlations.  Their article is both published in the May 2020 issue of Nature Materials and discussed in its News and Views section.

Emitting photons is one way to be cool

February 21, 2020

Shanhui Fan's lab at Stanford has proposed a new device to cool an object by causing it to radiate extra heat.   Their publication, recently published in Physical Review Letters, is featured in a focus article in Physics.

Distinguishing the best and brightest materials

A new technique for measuring quantum dot efficiency with 100 times better precision.

Cora Went's article is now published in the Frontiers in Energy Research Newsletter: Winter 2020.

EFRC Newsletter Editorial Board

September 19, 2019

Cora Went, PhD student in Professor Harry Atwater's group at Caltech, was selected to serve on the Editorial Board for the DOE's EFRC newsletter, Frontiers in Energy Research.

Congratulations Cora!







September 2019 Meeting at Stanford

The PTL team met at Stanford on September 9-10, 2019.  Thanks to everyone for a successful meeting full of great presentations, discussions and brainstorming. 



EFRC Directors' Meeting in Washington, D.C. 

PTL researchers presented their work at the DOE-EFRC PI meeting in D.C. on July 29-30, 2019.  Thanks, DOE BES for organizing a great workshop!


Nonmonotonic band gap evolution in bent phosphorene nanosheets

Eran Rabani and researchers show that fundamental band gaps of phosphorene sheets can be manipulated by as much as 0.7 eV depending on the bending direction.  Their work was published in Physical Review Matter on June 7, 2019.  (article)


Self-sustaining Thermophotonic Circuits

Researchers from Shanhui Fan's group demonstrate that a self-sustaining thermophotonic circuit can be constructed with the potential of significantly enhancing the power density of heat engines that use photons as the working medium.  Their article "Self-sustaining Thermophotonic Circuits" was published in the Proceedings of the National Academy of Sciences on May 22, 2019.  (article)


Spatiotemporal Light Control with Active Metasurfaces

Researchers from Mark Brongersma's group review recent developments toward time-varying metasurfaces and explore the opportunities that adding dynamic control can offer in terms of actively controlling the flow of light.  Their article, "Spatiotemporal Light Control with Active Metasurfaces," was published in Science on May 17, 2019.  (article)


Variational Theory of Nonrelativistic Quantum Electrodynamics

Researchers from Prineha Narang's group have developed a variational theory of general non-relativistic QED systems of coupled light and matter.   Their letter, "Variational Theory of Nonrelativistic Quantum Electrodynamics," was published in Physical Review Letters, May 16, 2019.  (article)







Spotlight Archive