Wits Researchers Tailor Quantum States of Light

Researchers from the School of Physics at Wits University, in collaboration with the Universitat Autònoma de Barcelona, have demonstrated the engineering of quantum light in both space and time to create high-dimensional and multidimensional quantum states. Published as a review article in Nature Photonics, the study surveys recent advances in techniques—including on-chip integrated photonics and nonlinear optics—capable of creating, manipulating, and detecting structured light. This tailoring of quantum states, where light’s spatial, temporal, or spectral properties are deliberately shaped, offers new pathways for high-capacity quantum communication and advanced quantum technologies, potentially increasing information capacity per photon and improving resilience to noise.

Engineering Quantum Light for Enhanced Technologies

Researchers at Wits University and the Universitat Autònoma de Barcelona have demonstrated the engineering of quantum light – specifically, controlling photons in space and time – to create high-dimensional and multidimensional quantum states. This tailoring of quantum light enables new pathways for high-capacity quantum communication and advanced technologies like imaging and sensing. Published in Nature Photonics, the review highlights rapid advancements in techniques including on-chip integrated photonics, nonlinear optics, and multiplane light conversion, representing a modern toolkit for manipulating quantum states.

A key benefit of structuring photons is the ability to access high-dimensional encoding alphabets, which allows for more information to be carried per photon and greater resilience to noise – crucial for secure quantum communication. While progress has been made, the source notes that current transmission distances with structured light are limited compared to traditional methods like polarization. This limitation is, however, driving research into abstract degrees of freedom and topological properties to preserve quantum information even with fragile entanglement.

The research indicates a turning point for the field, with developments in multidimensional entanglement, ultrafast temporal structuring, and on-chip sources capable of processing quantum light at higher dimensions. Applications include high-resolution quantum imaging, precision metrology, and quantum networks with increased capacity through multiple channels. Further work is needed to increase dimensionality, boost photon numbers, and engineer states robust enough for real-world optical environments, but the future “looks very bright indeed.”

Advancements in Techniques for Structuring Photons

Researchers at Wits University and the Universitat Autònoma de Barcelona have documented rapid advancements in techniques for structuring photons – deliberately shaping light’s spatial, temporal, or spectral properties. This work, published in Nature Photonics, highlights the creation of high-dimensional and multidimensional quantum states, utilizing tools like on-chip integrated photonics, nonlinear optics, and multiplane light conversion. The ability to tailor quantum light unlocks potential for next-generation communication, sensing, and imaging technologies, representing a significant shift in the field over the past two decades.

Structuring photons provides benefits by enabling access to high-dimensional encoding alphabets, which allows for more information per photon and improved resilience to noise – critical for secure quantum communication. While progress has been made, the source notes limitations in long-distance transmission of spatially structured photons due to unfavorable channel conditions. Current research is exploring solutions like imbuing quantum states with topological properties, aiming to preserve quantum information even when entanglement is fragile.

Recent developments also include advancements in multidimensional entanglement, ultrafast temporal structuring, and nonlinear quantum detection schemes. These innovations are driving applications like high-resolution quantum imaging, precision metrology, and quantum networks capable of carrying more information through multiple channels. According to Professor Forbes, the future looks “very bright indeed,” but further work is needed to increase dimensionality, boost photon numbers, and engineer states robust enough for realistic optical environments.

Applications and Future Directions of Quantum States

Researchers at Wits University have demonstrated the engineering of quantum light in both space and time to create high-dimensional and multidimensional quantum states. This work, detailed in a Nature Photonics review, highlights advances in techniques like on-chip integrated photonics and nonlinear optics. Structuring photons—deliberately shaping their spatial, temporal, or spectral properties—offers new avenues for high-capacity quantum communication and advanced quantum technologies, potentially impacting fields like imaging and sensing.

A key benefit of structuring photons is accessing high-dimensional encoding alphabets, allowing for more information per photon and greater resilience to noise, which is crucial for secure quantum communication. While progress has been significant—with compact and efficient on-chip sources now available—challenges remain in achieving long-distance transmission due to limitations in current channels. Researchers are exploring solutions like imbuing quantum states with topological properties to preserve quantum information, even with fragile entanglement.

The study points to an inflection point in the field, with rapid developments in areas like multidimensional entanglement and ultrafast temporal structuring. Potential applications include high-resolution quantum imaging, precision metrology, and quantum networks capable of carrying more information through multiple channels. Further research is needed to increase dimensionality, boost photon numbers, and create states robust enough for realistic optical environments, but the future “looks very bright indeed.”

The tailoring of quantum states, where quantum light is engineered for a particular purpose, has gathered pace of late, finally starting to show its full potential. Twenty years ago the toolkit for this was virtually empty. Today we have on-chip sources of quantum structured light that are compact and efficient, able to create and control quantum states.

Professor Andrew Forbes
Quantum News

Quantum News

As the Official Quantum Dog (or hound) by role is to dig out the latest nuggets of quantum goodness. There is so much happening right now in the field of technology, whether AI or the march of robots. But Quantum occupies a special space. Quite literally a special space. A Hilbert space infact, haha! Here I try to provide some of the news that might be considered breaking news in the Quantum Computing space.

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