Lasers for Accelerators
Lasers are playing an increasingly important role in accelerator physics from laser plasma accelerators and photo injectors to diagnostic tools like laserwire and beam polarisation measurements. Our research focuses on laser development for the these applications primarily using fibre lasers. These have excellent spatial quality, efficiency, thermal management and pointing jitter compared with larger conventional solid state systems.
We are always happy to receive applications for DPhil projects from well qualified students. We have projects available in experimental and theoretical development of lasers for drivers of laser plasma acceleration. The Lasers for Accelerators (L4A) group at the JAI is a versatile team focused on several areas of cutting edge research in the boundary between accelerators and lasers. In particular, the group is developing an alternative method for laser plasma acceleration. Normally, the plasma oscillations are excited by a single extremely high intensity laser pulse, but it has been shown theoretically that large plasma oscillations can also be driven by a train of lower intensity pulses. This would enable the use of tabletop lasers for plasma acceleration, rather than the use of national scale facilities. In this context, the L4A group is focusing on developing a suitable laser to drive plasma oscillations by a train of laser pulses in order to build a 1 GeV electron accelerator operating at 1 kHz. A PhD student project is available in this area within the John Adams Institute. The student would be working on developing new laser technologies in our laser lab in Oxford, including investigating methods of shaping a pulse train to efficiently excite a plasma oscillation. In conjunction with this work, the student would also be working on diagnostic methods for measuring the amplitude of plasma oscillation and using this to evaluate the best laser pulse trains for excitation. The project would therefore be primarily experimental in nature, and suit a student with an interest in laser or accelerator science. However, there is scope for the student to develop theoretical and simulation work, especially on the plasma and diagnostics side of the project.
The L4A group is also involved in all areas of interaction between accelerators and lasers and optics. This can cover areas ranging from the use of new laser technology for particle measurement to using lasers to actually accelerate the particles and everything in between, including the evaluation of optical fibres for data transport with radiation hard accelerator environments. A project the L4A group has been involved in for several years, in collaboration with RHUL and the Japanese High Energy Research Organisation (KEK), is the laserwire experiment to measure particle beam sizes of <1 micron. A laserwire is often the only method to measure the transverse size of electron bunches in a high intensity, well collimated electron beam, as foreseen for example by ILC, CLIC and new synchrotron radiation sources. For the laserwire project, the group has developed a special laser using photonic crystal rod fibre which delivers the required high energy laser pulses with exceptionally high mode quality.
For more information, contact Dr. L. Corner (l [dot] corner1 [at] physics [dot] ox [dot] ac [dot] uk) or Dr. R. Walczak (r [dot] walczak1 [at] physics [dot] ox [dot] ac [dot] uk) and see the Particle Physics gradute admissions page: https://www2.physics.ox.ac.uk/study-here/postgraduates/particle-physics For more information on the L4A group, visit our website (link below).
