Prof. Brian Smith
University of Oxford
时间：7月7日（周一）上午9:30
地点：唐仲英楼 A313
Abstract：
Improved measurement techniques are central to technological development and foundational scientific exploration. Quantum physics relies upon detectors sensitive to non-classical features of quantum systems, enabling precise tests of physical laws and quantum-enhanced technologies such as precision measurement and secure communications. Accurate detector response calibration for quantum-scale inputs is key to future research and development in these cognate areas. To address this requirement quantum detector tomography (QDT) has been recently introduced. However, the QDT approach becomes increasingly challenging as the complexity of the detector response and input space grows. Here we present the first experimental implementation of a versatile alternative characterization technique to address many-outcome quantum detectors, characterizing a balanced homodyne detector. To demonstrate the applicability of this approach the calibrated detector is subsequently used to estimate non-classical photon number states.
Biography：
Prof. Brian Smith received his Ph.D. in Physics from the Oregon Center for Optics within the Physics Department at the University of Oregon in 2007. He held a Royal Society Research Fellowship at the University of Oxford from 2007 to 2009. He was a Research Fellow in the Centre for Quantum Technologies at the National University of Singapore from 2009 to 2010, when he returned to the University of Oxford where he is currently Associate Professor in Experimental Quantum Physics. He founded and leads the Oxford Optical Quantum Technologies research group. His research has focused on the production and characterization of quantum states light and their applications. This includes implementation of the first controllable photonic quantum circuits, the first development of methods for measuring the transverse-spatial quantum state of light and approaches to engineering the quantum state of light created via spontaneous four-wave mixing in optical fibres. His current work examines the creation, manipulation and characterization of the time-frequency and amplitude-phase states of light. Examples of this include high-efficiency heralded pure state multi-photon sources, number-resolving detection capabilities, and control of photonic quantum coherences using non-classical interference and measurement.