The Journal of Physics B describes the collection of papers as ‘exceptional’ and ‘a taste of some of the most outstanding and excellent research published in Journal of Physics B: Atomic, Molecular and Optical Physics in 2010’.
Will Bryan’s paper, ‘Multi-pulse scheme for enhancing electron localisation through vibrational wavepacket manipulation’ discusses the manipulation of bound electrons in molecules with laser pulses only a few cycles in duration. This work continues recent experiments imaging and controlling a vibrational wavepacket on the femtosecond timescale, allowing electron dynamics on the attosecond timescale to be probed. By tailoring the temporal shape of the oscillating electric field in a laser pulse, it has been demonstrated that an electron can be made to hop between nuclei in a controlled manner. By considering the interaction between the nuclear and electronic motions, the electron is predicted to be localized on one nucleus with a probability above 80%. Such manipulation has applications in engineering chemical dynamics on the scale of individual molecules, and quantum information processing. This work was co-authored with his collaborators from Queen’s University Belfast and University College London, who carry out experiments using the Artemis Laser Facility at the Rutherford Appleton Laboratory in Oxfordshire.
Stefan Eriksson’s paper, ‘Atom chip for BEC interferometry’ describes how to make microscopic circuits of trapped ultracold atoms on a chip, and how to use cold atoms for interferometry. The interference effects are otherwise similar to those seen in the famous double slit experiment normally conducted with light, but on the atom chip the light waves are replaced by atomic matter waves. Another crucial difference which presents both challenges and opportunities in the atom chip experiment is that unlike photons the cold atoms interact both with each other and with the environment. The atom chip was used to show for the first time how sensitively matter-waves in a double well Bose-Einstein condensate can be used to measure small energy differences. Results published in Physical Review Letters show that the interferometer can be used to measure weak atom-surface interactions such as the Casimir-Polder force. Understanding surface forces is vital both for fundamental studies of physics at short ranges and applications involving micro and nano scale machines. The work was carried out in collaboration with the Centre for Cold Matter at Imperial College and the University of Southampton.
Stefan is also a member of the ALPHA Collaboration, led by Professor Mike Charlton also from Swansea Physics Department. The collaboration, whose project is based at CERN in Geneva, recently announced a breakthrough in a major international experiment to study antimatter closely for the first time. Details of the breakthrough are available at http://www.swan.ac.uk/physics/news/antimatterbreakthrough.php
The full 2010 Highlights Collection, including the two papers above, is available from http://iopscience.iop.org/0953-4075/page/Highlights%20of%202010 until 31 December 2011.
More information on Will and Stefan's research interests can be found on their personal research web pages at http://www.swansea.ac.uk/staff/academic/physicalsciences/bryanw/ and http://www.swan.ac.uk/staff/academic/physicalsciences/erikssonsj/