D. J. Thompson, D. Murphy, R. W. Speirs, R. M. W. van Bijnen, A. J. McCulloch, R. E. Scholten, B. M. Sparkes Physical Review Letters 117, 193202 (2016) [pdf] Imaging with electron and ion beams is slow because the charges repel each other. Beams of electrons or ions diffuse because the particles repel each other […]
blogs.unimelb.edu.au/atomopt/2016/11/07/new-publication-suppression-of-emittance-growth-using-a-shaped-cold-atom-electron-and-ion-source
The fabrication of ever-shrinking semi-conductor devices requires focused ion milling sources with smaller and smaller resolution. To achieve the sub-nanometre focusing potential of a cold atom electron and ion source (orders of magnitude smaller than thermal sources) will require the removal of any heating mechanisms, such as disorder-induced heating. One way of overcoming this effect […]
blogs.unimelb.edu.au/atomopt/2016/08/15/new-publication-disorder-induced-heating-of-ultracold-neutral-plasmas-created-from-atoms-in-partially-filled-optical-lattices
New electron sources using laser-cooled atoms promise breakthrough enhancements in brightness with potential for ultrafast imaging at atomic scales. In these sources the beam current is intrinsically tied to the efficiency of excitation of the cold atoms. Here we present experiments where we use the counter-intuitive STIRAP technique to increase the excitation efficiency and therefore […]
blogs.unimelb.edu.au/atomopt/2016/08/15/new-publication-stimulated-raman-adiabatic-passage-for-improved-performance-of-a-cold-atom-electron-and-ion-source
This invited article reviews cold atom electron sources, describing the many different implementations of the concept and an overview of the relevant theory behind their operation. We compare results from recent cold electron diffraction experiments with typical results achieved using conventional thermal sources, highlighting the potential of cold atom sources for single-shot and ultrafast diffraction […]
blogs.unimelb.edu.au/atomopt/2016/08/04/new-publication-cold-electron-sources-using-laser-cooled-atoms
Stabilisation of laser frequency is essential for numerous applications, including atomic clocks, laser cooling and trapping of atoms, and Bose-Einstein condensation. We have shown that polarisation spectroscopy can achieve frequency narrowing to below 1kHz. The method is inherently tied to an absolute atomic resonance, and relatively simple compared to the more common approach of locking to an […]
blogs.unimelb.edu.au/atomopt/2016/05/25/new-publication-sub-kilohertz-laser-linewidth-narrowing-using-polarization-spectroscopy
Our article Single-shot electron diffraction using a cold electron source, has been selected by the Editors of Journal of Physics B:Atomic, Molecular and Optical Physics for inclusion in their ‘Highlights of 2015’ collection due to “its outstanding quality and impact within the field of AMO physics”. Reference: R. W. Speirs, C. T. Putkunz, A. J. McCulloch, […]
blogs.unimelb.edu.au/atomopt/2016/03/08/single-shot-cold-electron-diffraction-paper-selected-in-highlights-of-2015-by-editors-of-j-phys-b
We have shown that the phenomena of Rydberg blockade can be used to increase the ordering of ions in a cold expanding bunch, leading to an increase in focusability for our cold atom ion source. Reference: D. Murphy, R. E. Scholten, B. M. Sparkes, Physical Review Letters 115, 214802 (2015) [pdf]
blogs.unimelb.edu.au/atomopt/2015/11/24/new-publication-increasing-the-brightness-of-cold-ion-beams-by-suppressing-disorder-induced-heating-with-rydberg-blockade
Welcome to the Atomic and Quantum Optics research group at the School of Physics, University of Melbourne. Here, we study how light interacts with all sorts of quantum systems and ways we can tailor this interaction for useful purposes. We have three main research directions: Ultracold atoms, ions and electrons: using techniques from laser cooling […]
blogs.unimelb.edu.au/atomopt/2015/10/29/hello-world