A hybrid platform providing a step forward in quantum technologies

A recent publication in Nature Physics by researchers at Te Whai Ao — Dodd-Walls Centre for photonic and quantum technologies and the University of Otago has introduced a new method for controlling hybrid systems.

Together with the Vienna University of Technology, they’ve created a novel technique that could be applied to quantum computing and quantum sensing.

The study was conceived and led by Dr. Nicholas Lambert, working with Associate Professor Jevon Longdell and Professor Harald Schwefel. In the paper, entitled “Coherent control of magnon-polaritons using an exceptional point” the team studied a cavity magnonic system, in which the excitations of a magnetic material are coupled to photons at microwave frequencies. In such systems, a loss of energy is usually regarded as a negative; in this work, energy loss is shown to be a powerful tool for system control.

A magnon-polariton is a hybrid particle formed by the coupling of a magnon (a quantum of magnetic excitation) and a photon (a particle of light). This coupling results in a new state of matter that inherits properties from both magnons and photons and allows the system to be fine-tuned for a number of applications in quantum technologies. Cavity magnon-polaritons have also received attention for potential applications in quantum networks due to their unique properties and tunability.

Dr Lambert says this form of coherent control provides a new tool to prepare a quantum state, which is essential for quantum computing amongst other applications.

“The highly controllable nature of our hybrid platform provides a new avenue for exploring the intriguing dynamic properties of coupled systems,“ he says.

As well as being a powerful tool to investigate the physics of energy loss and gain, the novel platform offers a way to manipulate hybridised states in a variety of systems.  The next step for the researchers is to extend their techniques to the quantum regime.

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