The Wonderful World of DECOHERENCE
Decoherence is widely advocated as a panacea to explain how complex quantum systems behave classically. Viewed as a physical process, decoherence is widely recognised to be the single biggest obstacle to quantum computing. It is also discussed in contexts as varied as the early universe, mesoscopics and nanoscience, biophysical systems, and large‐scale quantum phenomena in condensed matter and optical systems. But how does decoherence, and what are the mechanisms causing it? And is decoherence really “the answer to all our problems”? I will argue that the last few years have seen a very deep advance in our understanding of decoherence. Only very recently has any kind of quantitative agreement been reached between predictive theory and real experiments for complex quantum systems, in investigations of decoherence on large multi‐spin magnetic molecules. These experiments test at least 3 different decoherence mechanisms simultaneously, involving both ‘spin bath’ and ‘oscillator bath’ environmental decoherence. Theory also predicts new decoherence mechanisms which have not yet been investigated, such as ‘3rd‐party decoherence’; and exciting new frontiers are opening in this field, including ideas about the role of decoherence in some biological processes. Behind all of these developments is the suspicion that there may even be ‘intrinsic decoherence’ processes in Nature, which can never be suppressed. This talk will introduce a general audience to this topic, focusing on the recent progress (theoretical and experimental), and on some of the outstanding questions.
Event date: 22.06.2010, 14:00 to 22.06.2010, 16:00Speaker: Philip Stamp (Pacific Institute of Theoretical Physics, UBC, Vancouver, Canada)
Location: Christian-Doppler-Hörsaal, 3rd floor, 1090 Vienna
