Quantum light has the potential to revolutionize the fields of medical imaging and quantum computing. Researchers from the University of Sydney and the University of Basel in Switzerland have made significant progress in manipulating and recognizing a limited number of photons that interact with each other.Â
By observing how light interacts with matter scientists have discovered that light was not just a bunch of particles traversing through space, not a wave carrying energy but both, light exhibits both the characteristics of wave and particle, it is what scientists call wave-particle duality.
Quantum Light Emission
The way Light influences and interacts with matter fascinates scientists and their imagination on the topic not only due to its theoretical beauty but also due to the wide range of applications it has in different fields of technology. This could very well advance the field of Quantum Computing drastically.
Stimulated Light emission which was proposed by Einstein in 1916 is a phenomenon that is observed in almost all photons and forms the basis of LASERS, because of the research by the University of Sydney Stimulated Light emissions have also been observed in Single photons.
Dr. Sahand Mahmoodian from the University of Sydney School of Physics and Joint Lead Author on the research said that this research will pave the way to manipulate what they call ‘Quantum Light’.
He also added that this fundamental science will open pathways and pave the way to advancing Quantum-Enhanced measurement techniques and Photonic Quantum computing which many companies building Quantum Computers are using as their technology.
The fundamental science of understanding how light works is important, without that theoretical knowledge, modern technology would have been really hard to invent. No GPS, No Phones, No Medical Imaging, etc.
Light does not usually interact with itself and due to this characteristic, this can be very useful in communications using optic fibers that can lead to error-less, distortion-free transfer of data at light speed. But sometimes we very much do want light/ photons to interact with other photons and this is where the science gets complex.
 Light is used to measure small changes in instruments such as Interferometers. They are used in medical imaging or in sophisticated instruments such as LIGO which detected Gravitational waves in 2015. Also check: Concept behind our dreams.
The precision to make such measurements and the sensitivity it takes, the limits are set up by the laws of Quantum Mechanics. The limit is known to be set between the sensitivity required to carry on measurement and the no of photons used. Quantum light is different from classical laser light.
Dr. Natasha Tomm from the University of Basel, the Joint Lead Author on the research has said that the device they built was so very advanced and strong that they observed the device inducing strong photon interactions, that they were able to make out the difference in one photon interacting with it compared to two. One photon was delayed by a longer time compared to two photons, she said. She also added that with these powerful photon-photon interactions, the two photons become entangled in a two-photon bound state.
Conclusion
Quantum light like this has a way to revolutionize precision and sensitivity with which measurements are taken with better resolution all the while using fewer photons. This research has important practical applications in Medical Imaging, and Biological Microscopy, where large intensities of light can damage the sample used in an experiment, where the features to be observed are really small.
Dr. Mahmoodian revealed that his next focus for research is to utilize Quantum Light states to enhance the Fault Tolerance of Quantum Computers. This is a crucial step, considering that multi-million dollar companies like Psi Quantum and Xanadu are already investing in Quantum Computers.
According to Dr. Tomm, the research on Quantum Light is not only significant in validating the stimulated emission effect at its maximum limit, but it is also a remarkable technological advancement for various applications. Dr. Tomm further elaborated that this research can lead to the creation of more sophisticated devices that can generate multiple photon-bound states. These developments can have tremendous potential in fields such as Biology, Advanced Manufacturing, and Quantum Information Processing.
