BYU graduate student Siavash Mirzaei-Ghormish is having his research highlighted in the journal APS Physical Review Applied. His and Dr. Camacho’s paper, “Nonlinear Optical Binding”, presents a theory of optical binding that incorporates nonlinear optical interactions. Optical binding refers to a phenomenon in which particles are moved around and arranged by the power of a light source. Similar to how magnets can form arrangements and connections due to invisible magnetic forces, optical binding happens when tiny particles are moved into formations and patterns because of light.
Under low light, the particles scatter light, arrange into regular arrays, and behave in a more predictable, or linear, manner. However, the theoretical work of Ghormish’s research with Dr. Camacho shows that when the particles are illuminated by a stronger light, new forces emerge from nonlinear interactions, resulting in more unpredictable formations. These nonlinear forces form tighter and more reconfigurable formations that are not possible under a weaker illumination.
"By going beyond the typical linear models, we've uncovered completely new ways that nanoparticles can stably arrange themselves," explains Siavash Ghormish. "This opens up exciting possibilities for creating adaptable structures at the nanoscale."
One key finding is that nonlinear optical binding offers greater tunability and external control over the arrangement of nanoparticles. Because of how these particles act differently depending on the strength of a light, the patterns and shapes of the particles’ arrangements can be changed merely with the switch of a light.
Professor Ryan Camacho emphasizes the broader impact of this work: "Our findings demonstrate that nonlinear optical binding provides a powerful new tool for manipulating matter at the nanoscale. This could really move forward fields like high-precision sensing, metrology, and even our understanding of fundamental physics in the quantum realm."
Camacho also praised his student’s contributions: “Siavash really deserves a lot of credit for this work. His mathematical and physical insights leading to this result were stunning and elegant. One of the paper’s reviewers wrote that in his 20+ years reviewing papers he has never recommended a paper be published with no changes until he saw this manuscript.”
This research, supported by the National Science Foundation, has endless possibilities; it has the potential to help build machines or optical materials that adjust themselves by changing the light or lead to new kinds of optical materials, which are materials that respond to light in unique or useful ways. The results of this research also lay a foundation for future experimental efforts in the field of nonlinear quantum optical binding and may help scientists learn how gravity works at the smallest scales and how the tiny quantum world connects to the everyday world.