Quantum Information, Quantum Optics and Quantum Control Group

Over the last five years or so a vigorous new research community has emerged in the field of Quantum information - Quantum control - Quantum optics, QQQ.

This is a huge movement worldwide, with a community that is brought together by a common research theme of understanding and exploiting coherence and entanglement in quantum mechanics to realise new applications. This is an interdisciplinary field that cuts very widely across traditional university departmental divisions, including aspects of physics, chemistry, electrical engineering, materials science, computer science and mathematics. Within this broad area, physics is a very strong influence, including atomic, molecular and optical (AMO) physics, condensed matter physics and chemical physics.

Conventional information or data can be encoded into discrete or continuous states of physical systems that follow classical laws. Taking this over into the quantum world, quantum information can be encoded into the states of discrete or continuous quantum systems. It is known already that characteristic quantum phenomena such as superposition, entanglement and the irreversibility of quantum measurement enable tasks that cannot be achieved with conventional information, such as guaranteed secure communication or certain computations. Experiments to demonstrate these effects, potentially leading to new technologies, require precise quantum control of the appropriate systems, such as atomic, molecular, optical or condensed matter. The last decade or more has seen huge progress, leading to working quantum communication systems and the building blocks for quantum processors. Precise quantum control also has other applications. For example, increasing knowledge and understanding of the details of fundamental chemical processes show us how we might control these processes at the quantum level, by modulating the spectral phase and amplitude of ultrashort pulses of light so as to implement coherent control schemes for chemical reactivity. Such schemes generally use evolutionary computational methods to "teach" the modulator how to achieve a particular chemical outcome with a shaped pulse of light. The area of quantum optics embraces both the study and application of quantum states of the electromagnetic field, which could be propagating or trapped in cavities or resonators. For example, quantum states of light enable quantum communication and have application for quantum processing. They also enable precise control of, or interactions between, other quantum systems. Quantum optics also plays a key role in various precision metrology and standards applications.

QQQ covers a broad spectrum, from the foundations of quantum physics and information theory, through the investigation and control of fundamental physical and chemical phenomena, to new information and communication technologies and optical metrology and standards.