Quantum Entanglement of Electrons from Sunlight
For the first time in the world, physicists from the University of Ottawa (Canada) and the Max Planck Institute for the Science of Light (Germany) generated quantum entanglement of electrons directly from sunlight, without using a laser. This achievement, published on August 19 in the journal Optica, opens new possibilities for the development of quantum technologies.
Experimental Setup
The study utilized an experimental setup consisting of a Fresnel lens the size of a window and a special funnel that concentrates the collected sunlight into an optical fiber as thick as a human hair. The focused beam was directed onto a special crystal, where the generation of entangled photons took place. The researchers focused on polarization, the orientation of electromagnetic field oscillations, ensuring conditions under which the color and direction of light did not affect the polarization state of the photons.
The obtained photons were 94% in line with the ideally entangled state and violated Bell's inequality, which is a classical confirmation of the quantum nature of the phenomenon. Previously, high-energy lasers were used to create entangled photons, indicating a significant breakthrough in this field. Many leading physicists doubted the possibility of initiating nonlinear optical processes using sunlight; however, the results of the research refute these doubts.
This technology has the potential to reduce costs and simplify quantum systems, particularly for satellite encryption. Space satellites will be able to generate reliable encryption keys using free sunlight. The method will also benefit remote scientific stations and the scaling of quantum computing, opening new horizons for research in this promising field.
This discovery could radically change approaches to quantum encryption and computing, as it allows the use of an accessible and environmentally friendly energy source—sunlight.
The application of such technologies in satellite systems could significantly enhance the security level of communications and reduce costs associated with energy infrastructure. The quantum technologies derived from this research will not only expand capabilities in scientific research but could also find practical applications in various industries.
This groundbreaking achievement in generating quantum entanglement from sunlight is not only a significant step forward but also resonates with other recent advancements in the field. For instance, researchers in the U.S. have successfully transmitted entangled photons over 62 kilometers using urban fiber optic lines, showcasing the expanding possibilities of quantum communication technologies. Such developments highlight the rapid progress in harnessing quantum phenomena for practical applications.