In free space, the interaction between a single photon and an atom is typically very weak. By confining light and atoms in a high-quality optical resonator, the coupling strength can be increased until the probabilities for absorption and emission are on the order of unity. Under these conditions the distinction between what is light and what is matter becomes blurred. This is at the heart of the study of cavity quantum electrodynamics (CQED). To enter this regime of strong coupling requires an optical cavity with extremelyh high mirror reflectivies and microscopic mode volume. The technical constraints can be relaxed, however, when multiple atoms are present, as the coupling strength increases as the square root of the number of atoms. For large atom numbers, this can lead to collective strong coupling between light and matter in relatively modest cavities.
Our group has recently realised a novel kind of laser which is itself made from a laser-cooled gas of potassium atoms at a temperature of only one thousandth of a degree above absolute zero. This work highlighted a variety of interesting behaviours, such as random switching of the laser emission between two output directions, and a controllable breaking of symmetry between light passing forwards and backwards through the gas of atoms. We are currently studying the coherence properties of the laser, with an eye towards realising new kinds of active quantum technologies for precision timing, magnetometry, and rotation sensing.
This work involves a wide range of experimental components and techniques including lasers, electronics, computing, and ultrahigh vacuum. Conceptually, the focus is on quantum atomic and optical physics. Prior experience is a plus, but strong motivation and a patient, methodical approach are essential.
Funding and Eligibility Requirements
Funding is awarded by the school on a competitive basis, depending on the strength of the applicant. The funding is only available to EU citizens.
Non-EU Students: If you have the correct qualifications and access to your own funding, either from your home country or your own finances, your application to work on this project will be considered.
For details of the funding available please contact: [email protected]
For advice on making your application, please contact: [email protected]
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