New Physical Review Letters Paper is out

Researchers at Washington State University use Patterns to set Limits on Light/Matter Interactions

 

Physicists Rick Lytel, Sean Mossman, Ethan Crowell and Mark Kuzyk at Washington State University are developing general principles that can be applied to making new materials that harness light.   Beefed up light-matter interactions can be used to make higher-contrast medical images, more effectively burn cancer cells while leaving healthy ones intact, suppress the twinkle of stars in telescopes, supercharge the internet, make lasers more colorful and effortlessly process complex images.  The new has appeared in the August 18^th 2017 issue of Physical Review Letters.

Researchers typically model each new candidate material with complex equations that are difficult to interpret.  Rather than evaluate specific materials using this obtuse formalism, the WSU team instead studies the structure of the equations to search for patterns that hint at the largest possible response.  Since the equations are intractable, the researchers instead throw metaphoric darts at the target, but constrain the trajectories using the sum rules -- physical laws that must be obeyed by a quantum system.  After many throws, and applying a filter that takes into account the effect of molecule size, a pattern comes into focus.

The pattern reveals the true fundamental limits to be about 30% lower than previously calculated and suggests that a potentially new design paradigm will be required to get to the limit.  Ongoing work is aimed at translating the physicists’ esoteric findings into rules that can be used by chemists, materials scientists and nanotechnologists to make better materials.

The present work resolves several puzzles.  The theory of the fundamental limits of light/matter interaction strength predicted a ceiling that was almost 50% higher than all theoretical models, suggesting that exotic materials were needed to bridge the gap.  The new work shows that such unphysical quantum systems are not required to reach the limits and that exotic systems will likely obey the same limit.  Furthermore, infinities in the older incomplete theory – warning flags in physics of theoretical pathologies -- have been excluded by the new results.

While the present work has practical implications for new technologies, the search for patterns generated by constrained random sampling is a powerful tool that can be applied to understanding the underlying structure of complex theories.  In future work, the WSU researchers plan to apply this approach to a holistic investigation of the combined properties of a material needed for specific applications, and identifying the path for getting there.