Researchers from NIST and the Joint Quantum Institute have developed a new method to control the light emitted by quantum dots using pairs of lasers. This technique could significantly improve quantum dots as a source of entangled photons, which are crucial for advanced cryptography and quantum communication technologies.
Quantum dots are nanoscale semiconductor regions that behave similarly to single atoms. However, imperfections in their shape cause energy levels to separate, ruining the ideal state needed for entangled photon emission. The NIST-JQI team used lasers to precisely control the energy levels of quantum dots, similar to how physicists manipulate single atoms.
By adjusting the intensity of the laser beams, the researchers were able to correct for imperfections and generate more ideal signals. Their compact device, which operates in a liquid helium bath, demonstrates the potential for efficient, reliable entangled photon generation. This breakthrough could accelerate the development of quantum information technologies and pave the way for more complex quantum systems and devices.
Source: https://www.nist.gov/news-events/news/2008/08/light-touch-controlling-behavior-quantum-dots
Keywords: Entanglement, Quantum Dots, Laser manipulation, Quantum Cryptography, Photon Emission
