Researchers at NIST have discovered that quantum dots made of indium arsenide and gallium arsenide (InAs/GaAs) – previously thought to be stable light sources – actually exhibit fluorescence intermittency or “blinking.” This blinking, while brief (nanoseconds to milliseconds), can cause efficiency losses that could hinder their use in quantum computing and quantum telecommunications.
The NIST team found that when quantum dots are incorporated into photonic structures (as required for many applications), their radiative efficiency drops to between 50-80%, far below the 100% efficiency needed for future quantum technologies. The blinking is thought to be caused by defects introduced during device fabrication.
The study suggests that while InAs/GaAs quantum dots may be promising single photon sources, their stability and efficiency must be carefully considered when designing photonic structures for quantum applications. Future research will focus on understanding how different device geometries can minimize blinking while maintaining high photon transmission efficiency.
Keywords: fluorescence, quantum, photon
