Physics for future technology
4 October 2007
Four UCL projects are featured in a new booklet highlighting the UK's world-class contribution to the commercial application of physics.
The booklet focuses on condensed matter physics and is the first in the series 'Physics for Future Technologies' covering the main areas of physics. The series is published by the Institute of Physics and the Engineering and Physical Sciences Research Council.
Research into condensed matter underpins much of the technology we use today, and represents one of the most important areas of physics. It covers both solids and liquids, with the aim of understanding their physical properties in terms of their atomic and molecular structure and behaviour. Many of the materials and products we rely on today such as washing-up liquid, plastic products and paint were developed through this kind of knowledge.
A handful of research groups across the UK are interested in harnessing the electronic, optical and magnetic properties of metal nanoparticles to diagnose and treat disease. UCL's Professor Quentin Pankhurst (London Centre for Nanotechnology) and his group use magnetic nanoparticles for cancer detection and treatment. By applying an exterior magnetic field, injected nanoparticles in the patient can be heated up to a temperature where they will kill targeted cancer cells.
The team has also created a spin-out company, called Endomagnetics, which has commercialised a hand held probe that can help surgeons tell if breast cancer has spread to the patient's lymph nodes. Magnetic nanoparticles - tagged with molecules that can detect cell receptors specific to cancer cells - are injected into the patient. The hand held probe can check if the cancer has spread or not by detecting the magnetic particles.
Carbon is one of the most versatile of all the elements, existing in many different forms as well as being the basis of life. Researchers are exploring its excellent properties of conductivity for an array of commercial applications. UCL's Dr Mark Ellerby, Dr Tom Weller and Professor Neal Skipper (London Centre for Nanotechnology) have made two completely new compounds of graphene with ytterbium and calcium atoms sandwiched between layers of carbon.
With colleagues at the University of Cambridge, they discovered that the two compounds unexpectedly became superconducting at 6.5 and 11.5 Kelvin respectively, much higher temperatures than previously been found with other compounds and much easier to work with.
These new discoveries have the potential to develop in to new technologies by manipulating graphite's electronic properties and replace metals, superconductors and magnets at the nanoscale.
Advancements in telecommunications and computing lead to constant demands on scientists and engineers to get the maximum productivity from electronic chips while reducing the chips in size. However, there is a limit to the size silicon chips will function at, so Professor Alexander Shluger, Dr David Munoz Ramo and Dr Jacob Gavartin (UCL Physics & Astronomy and LCN) have been investigating hafnium oxide as an alternative to silicon dioxide, in an effort to reduce chip size. Not much is known about this material, but it has a tendency to suffer from defects that trap electronic charge. The team have been producing computer models of the compound in an effort to try and understand the causes of the trapping.
Eventually, computing capabilities will be demanded at such a small scale that other materials and technologies will take over from what we are familiar with today. One possibility explored by Professor Marshall Stoneham (UCL Physics and Astronomy) uses electron spins controlled by a laser in a way that is compatible with the silicon technology of near-future fabrication plants, with the added advantage of being able to work at room temperature, unlike most quantum computing schemes.
To find out more, use the links at the top of this article
Image 1: Endomagnetics
Image 2: Superconducting graphite