Research conducted by scientists at University of Oklahoma Now published in Scientific progress Establishes the validity of the idea that information can be securely encoded and transmitted using spatial correlations in quantum-entangled light beams.
LIGHT can be used to encrypt data for transmission at high data rates, long distances, and other purposes. To protect the privacy and integrity of transmitted data, encoding large amounts of information in light adds additional difficulties to secure communication.
The study’s first author, OU doctoral student Gaurav Nirala, and co-authors Shiva T. Pradyumna and Ashok Kumar to conduct research with Homer L. Worked with Alberto Marino, Ted S. Webb Presidential Professor at Dodge College of the Arts.
In addition, Marino maintains positions at the Quantum Science Center at Oak Ridge National Laboratory and the Quantum Research and Technology Center at the University of Oklahoma.
The idea behind the project is that the spatial properties of light can be used to encode large amounts of information, just as an image contains information. However, it can do so in a way compatible with quantum networks for secure information transfer. When you consider an image, it can be constructed by combining basic spatial patterns known as modes, and depending on how you combine these modes, you can change the image or the encoded information.
Alberto Marino, Ted S. Webb Presidential Professor, Homer L. Dodge College of the Arts
He added, “What we do here is new and different and we use correlations between them. We use additional information about how those modes are connected to encode the information.“
The researchers used two entangled light beams, meaning that the light waves are coupled with stronger correlations than can be achieved with classical light, even though they are far apart.
“The advantage of the approach we introduce is that you cannot recover the encoded information unless you perform joint measurements of the two trapped beams. It has applications like secure communication, and if you measure each beam yourself, you won’t be able to extract any information. To extract the encoded information you need to get the shared information between the two beams and combine them properly.Marino added.
Through a series of images and correlation studies, the researchers showed the effects of correctly encoding the information in these quantum-entanked light beams. When the two beams meet as expected, the information is resolved into only recognized information stored in the form of images.
The experimental result describes how spatial patterns can be transferred from one optical field to two new optical fields created using a quantum mechanical process called four-wave mixing. The encoded spatial pattern can only be recovered by combined measurements of the generated fields. An interesting aspect of this experiment is that it offers a novel way to encode information in light by modifying the correlation between different spatial modes without affecting time-correlations.
Gaurav Nirala, first author of the study and a postdoctoral student at the University of Oklahoma
Marino concluded, “What this enables is, in principle, the ability to securely encode and transmit large amounts of information using the spatial properties of light, much like turning light on and off in an image. A new approach to encoding information uses spatial correlations.“
Nirala, G. etc. (2023) Information encoding in spatial correlations of entangled twin beams. Materials Chemistry Frontiers. doi:10.1126/sciadv.adf9161.