Computers and electronic gadgets, such as the iphone, have transformed modern life. The silicon transistor is at the core of this revolution, having been continuously made faster and smaller over the last forty years. In a chip, millions of them are squeezed into an area the size of a pinhead, switching a billion times in one second. Transistor size has now reached nanometre dimensions; one nanometre is only ten time larger than an atom. Moore's law, which dictates that transistor size halves every two years and is the driving force behind the success of the electronics industry, has come to a halt. The happy and easy days of transistor scaling are now gone. Quantum mechanical laws conspire against transistor function making it leak when switched off and generating poor electrical control. Also, our inability to control the precise atomic structure of interfaces and chemical composition during fabrication makes transistors less predictable. Hence semiconductor companies are searching for alternative, non-planar (multigate) transistor architectures and novel devices such as nanowires, nanotubes, graphene and molecular transistors, which will ultimately break through the nano-size barrier resulting in a completely new era of miniaturization. There is a significant gap between our ability to fabricate transistors and to predict their behaviour.The simulation and prediction of the silicon transistor has become an vital mission. Current planar transistor architecture presents serious problems in scalability regarding leakage and controllability. Transistors of nanometre dimensions are more vulnerable to the atomic nature of matter than their previous cousins of micrometre dimensions. Furthermore, at nanoscales heat transfer is a source of heat death for novel transistor applications due to the decrease of thermal conductivity. Within this context I propose to develop a Quantum Device simulator, with atomic resolution that will enable the accurate prediction of present and future transistor performance. The simulator will deploy a quantum wave description of electron propagation, treating the interaction of electrons with crystal lattice vibrations (heat) at a fully quantum mechanical level. It will have the capability of describing the electron interactions with the roughness of the semiconductor/dielectric interface and with each other under the effect of a high electric field. Devices will be properly tested and optimised regarding materials, chemical composition and geometry without the high costs implicit in fabrication. A wide range of transistors will be explored from planar, non-planar and novel. This is timely as existing computer design tools lack predictive capabilities at the nanoscale and the industrial build-and-test approach has become prohibitively costly. Efficient quantum-models/algorithms/methodologies and tools will be developed.These are dynamic times as device dimensions move closer to the realm of atoms, which are inherently uncontrollable. In this regime two streams collide: the classical and quantum worlds making the need for new regularities and patterns vital as we strive to conquer nature at this scale. This offers exiting opportunities to merge an engineering top-to-bottom approach with a physics bottom-up approach. As 21st century environmental concerns rise, the need for greener technology is increasing. My proposal addresses the lowering of power consumption, raw material reductions delivering more functionality and the provision of a cheaper way to assess new design technologies. Collectively, these will help companies to provide a greener alternative to consumers.

Computers and electronic gadgets, such as the iphone, have transformed modern life. The silicon transistor is at the core of this revolution, having been continuously made faster and smaller over the last forty years. In a chip, millions of them are squeezed into an area the size of a pinhead, switching a billion times in one second. Transistor size has now reached nanometre dimensions; one nanometre is only ten time larger than an atom. Moore's law, which dictates that transistor size halves every two years and is the driving force behind the success of the electronics industry, has come to a halt. The happy and easy days of transistor scaling are now gone. Quantum mechanical laws conspire against transistor function making it leak when switched off and generating poor electrical control. Also, our inability to control the precise atomic structure of interfaces and chemical composition during fabrication makes transistors less predictable. Hence semiconductor companies are searching for alternative, non-planar (multigate) transistor architectures and novel devices such as nanowires, nanotubes, graphene and molecular transistors, which will ultimately break through the nano-size barrier resulting in a completely new era of miniaturization. There is a significant gap between our ability to fabricate transistors and to predict their behaviour.The simulation and prediction of the silicon transistor has become an vital mission. Current planar transistor architecture presents serious problems in scalability regarding leakage and controllability. Transistors of nanometre dimensions are more vulnerable to the atomic nature of matter than their previous cousins of micrometre dimensions. Furthermore, at nanoscales heat transfer is a source of heat death for novel transistor applications due to the decrease of thermal conductivity. Within this context I propose to develop a Quantum Device simulator, with atomic resolution that will enable the accurate prediction of present and future transistor performance. The simulator will deploy a quantum wave description of electron propagation, treating the interaction of electrons with crystal lattice vibrations (heat) at a fully quantum mechanical level. It will have the capability of describing the electron interactions with the roughness of the semiconductor/dielectric interface and with each other under the effect of a high electric field. Devices will be properly tested and optimised regarding materials, chemical composition and geometry without the high costs implicit in fabrication. A wide range of transistors will be explored from planar, non-planar and novel. This is timely as existing computer design tools lack predictive capabilities at the nanoscale and the industrial build-and-test approach has become prohibitively costly. Efficient quantum-models/algorithms/methodologies and tools will be developed.These are dynamic times as device dimensions move closer to the realm of atoms, which are inherently uncontrollable. In this regime two streams collide: the classical and quantum worlds making the need for new regularities and patterns vital as we strive to conquer nature at this scale. This offers exiting opportunities to merge an engineering top-to-bottom approach with a physics bottom-up approach. As 21st century environmental concerns rise, the need for greener technology is increasing. My proposal addresses the lowering of power consumption, raw material reductions delivering more functionality and the provision of a cheaper way to assess new design technologies. Collectively, these will help companies to provide a greener alternative to consumers.

How chloroplasts efficiently import thousands of different proteins. Chloroplasts and mitochondria are normal components of many cells - they are sub-cellular structures called organelles. Interestingly, these two organelles evolved from bacteria that were engulfed by other cells more than a billion years ago, and in many ways they still resemble free-living bacteria. Chloroplasts are found in plant cells, contain the green pigment chlorophyll, and are exclusively responsible for the reactions of photosynthesis (the process that captures sunlight energy and uses it to power the activities of the cell). Since photosynthesis is the only significant mechanism of energy-input into the living world, chloroplasts are of inestimable importance, not just to plants but to all life on Earth. Chloroplasts are also important in many other ways, since they play essential roles in the biosynthesis of oils, proteins and starch. Although chloroplasts do contain DNA (which is a relic from their ancient, evolutionary past as free-living photosynthetic bacteria), and are therefore able to make some of their own proteins, over 90% of the 3000 or so proteins required to build a fully functional chloroplast are encoded on DNA within the cell nucleus. The majority of chloroplast proteins are therefore made outside of the chloroplast, in the cellular matrix known as the cytosol. Since chloroplasts are each surrounded by a double membrane, or envelope, that is impervious to the passive movement of proteins, this presents a significant problem. To overcome the problem, chloroplasts have evolved a sophisticated protein import apparatus, which uses energy (in the form of ATP) to drive the import of proteins from the cytosol, across the envelope, and into the chloroplast interior. This protein import apparatus comprises two molecular machines: one in the outer envelope membrane called TOC (an abbreviation of 'Translocon at the Outer envelope membrane of Chloroplasts'), and another in the inner envelope membrane called TIC. This project is focused on the TOC machine, which performs two essential functions. Firstly, it recognizes those proteins that need to be imported as they arrive at the chloroplast surface. Secondly, it forms a channel through the outer membrane so that the proteins can pass across, once recognized. We will study the first of these functions: recognition. To carry out this function, the TOC machine uses special molecules called receptors, which bind to the proteins as they arrive at the chloroplast envelope. Quite recently, we found that there are actually several different types of receptor, and we think that they probably exist so that chloroplasts can efficiently recognize all of the many different proteins they need to import. In other words, we think that each of the receptors has a degree of specificity for a particular subset of the proteins that must be imported. This project will test these ideas, since we think that the different types of receptor are very important, helping to ensure the formation of fully functional chloroplasts. Because chloroplasts carry out essential functions, and because protein import is essential for chloroplast development, it should come as no surprise to learn that plants without a functional chloroplast protein import machinery are unable to survive (in fact, they die at the embryo stage). Thus, chloroplast protein import is an essential process for plants. Similarly, since we are all ultimately dependent upon plant products for survival, it follows that chloroplast protein import is essential on a global scale. What is more, since chloroplasts play a major role in the synthesis of many economically important products (such as oils and starch), a more complete understanding of how these organelles develop may enable us to enhance the productivity of crop plants, or otherwise manipulate their products.