Five Lectures on Quantum Information Applications of Complex Many-Body Systems

Abstract

AbstractIn recent years it has been realized that utilizing the full potential of quantum mechanics enables one to perform certain particularly important computational tasks much faster than ever possible with conventional (classical) computing technology [1]. In addition, quantum mechanics enables completely novel forms of cryptograpy and communication [2]. For the above tasks it is essential to encode information in quantum mechanical versions of bits or “qubits” (quantum mechanical two-state systems), typical examples being the polarization of a photon or the spin of an electron. For quantum computation in particular, very large collections of qubits are required. In general, larger the collection of qubits, more powerful the quantum computer. While few qubit quantum processors are already available, increasing the number of qubits by significant amounts is a problem that needs to be solved before truly powerful quantum computers come into being. It is from this point of view that the current set of lectures can be motivated. Complex many-body systems, a typical example being magnets, are each natural collections of several continuously interacting qubits or other identical systems. Can this natural resource of qubits be exploited for quantum computation or at least for tasks allied to quantum computation such as building small automata for logic gates or even simply for constructing a connection bus between two quantum computers? These are some of the questions that we will try to address in our lectures.KeywordsEntangle StateQuantum ComputationSpin ChainQuantum CommunicationQuantum GateThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.