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Q Seminar Jeff Lundeen
>> YOUR LINK HERE: ___ http://youtube.com/watch?v=NZ5kwuTIU-U
Slides for this talk are available at http://www.photonicquantum.info/Q%20p... • • Title: Seeing is Believing: Direct Observation of the Wavefunction • • Abstract: Central to quantum theory, the wavefunction is a complex distribution associated with a quantum system. Despite its fundamental role, it is typically introduced as an abstract element of the theory with no explicit definition. Rather, physicists come to a working understanding of it through its use to calculate measurement outcome probabilities through the Born Rule. Tomographic methods can reconstruct the wavefunction from measured probabilities. In contrast, I present a method to directly measure the wavefunction so that its real and imaginary components appear straight on our measurement apparatus. At the heart of the method is a joint measurement of position and momentum that is made possible by weak measurement (a concept that I will attempt to demystify). I will describe an experimental example of the method in which we directly measured the transverse spatial wavefunction of a single photon. New experimental work extending this to mixed states will be presented as well. Our direct measurement method gives the wavefunction a plain and general meaning in terms of a specific set of operations in the lab. • • Related Papers: • • Nature, 474, 188 (2011). http://arxiv.org/abs/1112.5471 • Phys. Rev. Lett. 108, 070402 (2012). http://arxiv.org/abs/1112.3575 • • Biography: • • Dr. Jeff Lundeen received his undergraduate degree in Physics from Queen's University, Kingston, Canada. He then completed a Ph.D. in experimental Quantum Optics and Quantum Information in the group of Prof. Aephraim Steinberg at the University of Toronto, on the subject of Quantum Measurement. As an NSERC postdoctoral fellow, he joined the group of Prof. Ian Walmsley at the Clarendon Laboratory, University of Oxford. He led a Photonic Quantum Information subgroup, developing ways to generate, manipulate and characterize quantum light. After this he was a post-doctoral fellow in Dr. Morgan Mitchell's lab at ICFO -- Institut de Ciències Fotòniques, Barcelona, performing experiments with squeezed light. He is now a Research Officer in Quantum Radiometry at the National Research Council in Ottawa Canada.
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