Spin Chain Connectors, Entanglement by Measurements and Mesoscopic Quantum Coherence

Recent years have seen a rapid progress in two areas connectedwith quantum mechanics. Firstly, stimulated by the ability ofquantum mechanics to permit novel computation, there is now a world wideeffort to realize a quantum computer. Identifying viable ways toconnect and network such computers is an intrinsic part of thiseffort. This research could revolutionize information technology.Secondly, some mesoscopic systems have been shown to behavequantum mechanically in series of audacious experiments. By stretching the boundary of what we generally regard as the quantum world, they beg the question as to whether any system, however macroscopic, can be made to exhibitquantum behaviour in an appropriately designed experiment. Myresearch aims to push the boundaries of both the abovedevelopments. On the connecting and networking issue, I want to investigate how chains of spins (small one dimensional quantum magnets) can connect up quantum computers efficiently and how they can serve as a source of genuine qunatum mechanical correlations. I also want to explore whether detection of light from distant places in a efficient ways can entangle distant matter systems, even high dimensional ones. On the issue of pushing the boundaries of what we regard as the quantum world, I intend to explore whether by coupling a microscopic and a mesoscopic system one can probe the quantum nature of the latter.