IQIM Postdoctoral and Graduate Student Seminar

Abstract: Entanglement and decoherence are key physical processes, central to quantum information processing (amongst many other things). Both are hard to understand and quantify - indeed, the very definition of entanglement has been a problem for decades.

In this talk I will try to do two things:

(i) Explain entanglement and decoherence, and then show how one can define multipartite entanglement in terms of 'entanglement correlators', and find the dynamics for these. This basically solves the problem of how to define entanglement for multipartite systems.

(ii) Apply these ideas to 2 real systems, the LiHo rare earth system, and the Fe-8 molecular magnet system. They are both 'quantum Ising systems' (as are almost all systems currently being used for quantum information processing), in which the coupling to both nuclear spins and phonons plays a key role.

With these results in hand it will then be interesting to discuss the future of solid-state based quantum information processing systems.