How can one increase the maximum current which can flow in a superconductor without any resistance? Counter-intuitively the answer in some circumstances is to increase the dissipation (i.e. the energy losses) in the superconductor, as Paul Warburton and his colleagues from LCN and the University of Oxford show.
Due to their smallness, nanomechanical resonators can sense masses down to a few atoms in vacuum. They typically transduce added mass into a change in resonance frequency of an oscillating cantilever. Such a description of the sensor response, however, is deceptively simple. In reality, the sensor response is determined not only by the mass, but also by the rigidity of adsorbed material.
Researchers in Chicago and London have developed a method for controlling the properties of magnets that could be used to improve the storage capacity of next-generation computer hard drives.
Magnets that can readily switch their polarity are widely used in the computer industry for data storage, but they present an engineering challenge: A magnet’s polarity must be easily switched when writing data to memory, but be difficult to switch when storing or reading it.
High-temperature superconductors conduct electrical currents, without any resistance, up to temperatures above the boiling point of nitrogen. One of its “champions” is Bi2Sr2Ca2Cu3O10+δ (Bi-2223), a material that is superconducting up to a critical temperature of 110 Kelvin. Though high-temperature superconductors were discovered more than two decades ago (Nobel Prize 1987), the mechanism leading to their superconducting state is still far from understood.
The Molecular Beam Epitaxy (MBE) Facility of the Department of Electronic and Electrical Engineering and the LCN was opened by HRH The Princess Royal on 12 January 2010. The purpose of the new UCL Molecular Beam Epitaxy system is to create new and improved electronic and optical devices using special materials built by controlling their structure atom by atom.
Professor Franco Cacialli has become a fellow of the American Physical Society upon the recommendation of the Division of Materials Physics.
The London Centre for Nanotechnology researches spintronics and quantum computing: two of the most promising ways to scale computers down to ever smaller sizes. Microelectronics should already be renamed nanoelectronics since computer chips are now built on nanoscopic scales. Quantum computing could take this further by using single atoms to store and manipulate information.
This week New Scientist cover article by journalist Eugenie Samuel Reich describes how a special material called spin ice, co-discovered in 1997 by Professor Steven Bramwell of the London Centre for Nanotechnology has come close to revealing a secret of the universe.