University of Oxford
Materials

What if we could utilise the full potential of quantum mechanics to transform technology? Imagine a quantum version of the internet where secure communication is possible across the globe, ultra-fast computers that can solve problems in seconds, and sensors that can detect the smallest details in materials on an atomic scale. At the bottom of these technologies is the qubit – the basic building block of quantum systems. My research focuses on a special type of qubit: the single-molecular qubit, which could play an important role in making this vision a reality.

A qubit can take many forms, from trapped ions to superconducting circuits, but it can also be a molecule created in the lab. Molecular qubits are particularly interesting because they can be engineered at the atomic level, making them highly customisable for different applications. The information of a molecular qubit is stored in its electron spin, which can be controlled and tuned by the way the molecule is designed. We use light to encode information on the qubit, but we can also transfer the quantum information back to light, enabling long distance quantum communication.

My project focuses on the demonstration of single-molecular qubits, which are crucial for the transition from laboratory experiments to large-scale quantum technologies. With the help of photophysical principles, molecules are designed to be efficiently initialised into quantum states that allow them to function as highly sensitive qubits. A laser pulse places the qubit into this well-defined quantum state, followed by a microwave-frequency signal that manipulates its spin, and the final state is read out by converting the spin information back into light. This highly precise technique, also known as optically detected magnetic resonance (ODMR), can be used to sense the environment or to store and transport quantum information. Unlike many other quantum systems, the single-molecular qubits can be utilised and read out under ambient conditions – without the need for ultra-low temperatures or external magnetic fields. This versatility positions them as promising candidates for practical quantum technologies, bridging the gap between laboratory-scale experiments and real-world applications in quantum communication, computation, and sensing.