Research on efficiency of single photon emitters highlighted
When—and why—does a photon emitter not emit? Research in the Van de Walle group illuminates the issue.
Decades of optimization have resulted in fiber-optic cables that can transmit photons with extremely low loss. However, this low-loss transmission works only for light in a narrow range of wavelengths, known as the “telecom wavelength band.” Identifying quantum defects that produce photons at these wavelengths has proven difficult, but funding from the U.S. Department of Energy and the National Science Foundation (NSF) has enabled Mark Turiansky and coworkers to understand why that is. They described their findings in “Rational Design of Efficient Defect-Based Quantum Emitters,” published in the journal APL Photonics.
Their work explains why the efficiency of single-photon emission drastically decreases when the emission wavelength increases beyond the wavelengths of visible light (violet to red) to the infrared wavelengths in the telecom band. The model also allows the researchers to identify techniques for engineering emitters that are brighter and more efficient.
