Theory and Advanced Computation (TAC)

The Computational Quantum Electronics Group (CQE) explores the complex quantum worlds of ultra-fast photonics, designed functional materials and nanobio-technologies by means of advanced computer simulation techniques.

At the beginning of the 21st century research and technology has embarked on a journey to the THz-world and into nano-space. Examples are the conception of designed materials like quantum dots, carbon-nanotubes or functional photonic crystals, the controlled manipulation of single biological molecules or the observation and exploitation of quantum effects on ultra-fast time-scales. The conception of such innovative materials, systems and key technologies is possible by harnessing photons and electrons and directly exploiting the fundamental quantum nature of light and matter - elucidating the very nature as well as application of ultra-fast nonlinear and quantum phenomena. In nano-space, no longer can the state of a photon or an electron be considered independently from their environment. Neither can novel nano-devices be developed without taking into account the very influence the photons or electrons have on them. In the life sciences, the advances in photonics and the nano-technologies are enabling a number of revolutionary and ultra-sensitive spectroscopic and diagnostic tools for the study and manipulation of complex bio-molecules or cells.

The recently established Computational Quantum Electronics Group (CQE) headed by Professor Ortwin Hess comprises four research staff and six PhD students (with more members expected to join later). CQE focuses on the theory and supercomputer simulation of the fundamentals and applications of complex materials, devices and systems in ultra-fast photonics, nano-electronics and the biomedical sciences. The group participates in and co-ordinates international research projects and has recently attracted major funding to build up the Nano-Modeling Supercomputing Lab within the ATI. Current foci of CQE's research interests are large-scale computer simulations of the

• ultra-fast spatio-temporal dynamics of:
  • quantum dots and quantum dot lasers
  • high-power semiconductor optical amplifiers
  • microcavity and optically pumped semiconductor lasers

taking into account many-body effects and quantum-kinetic carrier-transport as well as systems constraints. Innovative control schemes based on delayed optical feedback are investigated. The group also uses three-dimensional Finite-Difference Time-Domain (FDTD) simulations to computationally explore

• material properties and the design of functional
  • layered planar photonic crystals and
  • inverse opals.

Most recent work includes the theory and computer modelling of

• spatio-temporal dynamics of molecular motors, and
• fundamentals in the quantum theory of nano-thermodynamics.

Strong collaboration within the ATI as well as with academic partners and companies in the UK, Germany, Finland, Spain and Denmark integrate the computer simulations with experimental and nano-technological efforts and link them with innovative market application.

Information on the Computational Quantum Electronics Group can be found at http://www.ati.surrey.ac.uk/CQE/.