For the physics researcher Andrew L. Yeats, a light-bulb moment led to an important new insight.

Last year, in the University of Chicago’s new physics laboratory illuminated by low-energy fluorescent lights, Mr. Yeats was puzzled by a persistent error in an experiment involving an exotic material known as a topological insulator, a class of materials that conducts electricity on the surface and edges but insulates on the interior.

To the graduate student’s amazement, the hunt for the unexplained “noise” that was contaminating his experiment has led to a new technique for rapidly drawing and erasing optical computing circuits. The scientists describe the construction of optical “gates,” which might be used to create light-based circuits that are similar to electronic circuits based on transistors.

The insight could have an impact on diverse applications, including quantum computing research, new types of precise sensors and possibly a new approach to computing.

The mystery of the “noise” was resolved when the scientists realized that the low-energy fluorescent lights in the lab emitted ultraviolet light at just the right wavelength to polarize the surface of the experimental material they were using.