Researchers from the University of the Witwatersrand in South Africa and Huzhou University in China have demonstrated a link between quantum entanglement and topology. Led by Professor Andrew Forbes and master’s student Pedro Ornelas, the team manipulated pairs of entangled particles without changing their shared properties.
This could allow for the preservation of quantum information even when entanglement is fragile. The research, published in Nature Photonics, could lead to new quantum communication protocols using topology as an encoding mechanism. The team will now focus on defining these new protocols and expanding the landscape of topological nonlocal quantum states.
Quantum Entanglement and Topology: A Groundbreaking Connection
Researchers from the Structured Light Laboratory at the University of the Witwatersrand in South Africa, led by Professor Andrew Forbes, and in collaboration with string theorist Robert de Mello Koch from Huzhou University in China, have made a significant breakthrough in quantum physics. They have demonstrated the ability to perturb pairs of spatially separated yet interconnected quantum-entangled particles without altering their shared properties. This experimental milestone allows for the preservation of quantum information even when entanglement is fragile.
The Role of Quantum Entanglement
Quantum entanglement, often referred to as ‘spooky action at a distance’, enables particles to influence each other’s measurement outcomes even when separated by significant distances. The researchers achieved this experimental milestone by entangling two identical photons and customising their shared wave-function in such a way that their topology or structure becomes apparent only when the photons are treated as a unified entity. This connection between the photons was established through quantum entanglement, as explained by lead author, Pedro Ornelas, an MSc student in the structured light laboratory.
The Importance of Topology in Quantum Physics
Topology, in this context, refers to a global property of the fields, akin to a piece of fabric (the wave-function) whose texture (the topology) remains unchanged regardless of the direction in which it is pushed. The role of topology and its ability to preserve properties can be likened to how a coffee mug can be reshaped into the form of a doughnut; despite the changes in appearance and shape during the transformation, a singular hole – a topological characteristic – remains constant and unaltered. In this way, the two objects are topologically equivalent.
Skyrmion Topology: A New Perspective
The nature of the topology investigated here, termed Skyrmion topology, was initially explored by Tony Skyrme as field configurations displaying particle-like characteristics. These concepts have since been realised in modern magnetic materials, liquid crystals, and even optical analogs using classical laser beams. In the realm of condensed matter physics, skyrmions are highly regarded for their stability and noise resistance, leading to advancements in high-density data storage devices.
In the early 1960s, Tony Skyrme introduced the concept that sub-atomic particles could be represented as excitations of a single quantum field, leading to the idea of a skyrmion – a topologically stable field configuration. While this concept was not widely adopted in its original context, it has found diverse applications in fields like condensed matter physics, acoustics, and optics.
Typically, skyrmions have been realized as localized fields and particles. However, this recent publication marks a significant breakthrough by presenting the first instance of a non-local quantum entangled state with skyrmionic characteristics. This is notable because, despite the lack of distinct topological structures in individual photons, the entangled state as a whole exhibits a non-trivial topology.
The Future of Quantum Communication Protocols
The researchers utilise topology as a framework to classify or distinguish entangled states. They envisage that this fresh perspective can serve as a labelling system for entangled states, akin to an alphabet. Similar to how spheres, doughnuts, and handcuffs are distinguished by the number of holes they contain, quantum skyrmions can be differentiated by their topological aspects in the same fashion. The team hopes that this might become a powerful tool that paves the way for new quantum communication protocols that use topology as an alphabet for quantum information processing across entanglement-based channels.
The Significance of the Findings
The findings reported in the article are crucial because researchers have grappled for decades with developing techniques to preserve entangled states. The fact that topology remains intact even as entanglement decays suggests a potentially new encoding mechanism that utilises entanglement, even in scenarios with minimal entanglement where traditional encoding protocols would fail.
Future Research Directions
The research team plans to focus their efforts on defining these new protocols and expanding the landscape of topological nonlocal quantum states. This groundbreaking research opens up new possibilities for quantum information processing and communication, potentially revolutionising the field of quantum physics.
“We achieved this experimental milestone by entangling two identical photons and customising their shared wave-function in such a way that their topology or structure becomes apparent only when the photons are treated as a unified entity,”
Pedro Ornelas
“The entanglement between our photons is malleable, like clay in a potter’s hands, but during the moulding process, some features are retained,”
Professor Andrew Forbes
“We aspire to see a similar transformative impact with our quantum-entangled skyrmions,”
Professor Andrew Forbes
“Our work presents a paradigm shift: the topology that has traditionally been thought to exist in a single and local configuration is now nonlocal or shared between spatially separated entities,”
Pedro Ornelas
“Similar to how spheres, doughnuts, and handcuffs are distinguished by the number of holes they contain, our quantum skyrmions can be differentiated by their topological aspects in the same fashion,”
Dr Isaac Nape
“We will focus our research efforts on defining these new protocols and expanding the landscape of topological nonlocal quantum states,”
Professor Andrew Forbes
Quick Summary
Researchers have successfully manipulated pairs of quantum entangled particles without changing their shared properties, demonstrating a link between quantum entanglement and topology. This breakthrough could lead to a new encoding mechanism for preserving quantum information, even in scenarios with minimal entanglement where traditional encoding protocols would fail.
- Researchers from the Structured Light Laboratory at the University of the Witwatersrand in South Africa, led by Professor Andrew Forbes, and in collaboration with Robert de Mello Koch from Huzhou University in China, have demonstrated a method to manipulate quantum entangled particles without altering their shared properties.
- The lead author of the study, Pedro Ornelas, explains that this was achieved by entangling two identical photons and customising their shared wave-function, making their structure apparent only when treated as a unified entity.
- The connection between the photons was established through quantum entanglement, a phenomenon that allows particles to influence each other’s outcomes even when separated by significant distances.
- The researchers used topology, a concept that refers to the preservation of properties despite changes in appearance or shape, to classify or distinguish entangled states.
- The research, published in Nature Photonics, could lead to new quantum communication protocols that use topology as an alphabet for quantum information processing across entanglement-based channels.
- The findings are significant as they suggest a potentially new encoding mechanism that utilises entanglement, even in scenarios with minimal entanglement where traditional encoding protocols would fail.
