Condensed Matter Seminar: Introduction to the quantum first detection problem
Prof. Eli Barkay, Bar Ilan University
We consider quantum dynamics on a graph, with repeated strong measurements performed locally at a xed time interval . For example a particle starting on node x and measurements performed on another node x0. From the basic postulates of quantum mechanics the string of measurements yields a sequence no,no,no, and nally in the n-th attempt a yes, i.e. the particle is detected. Statistics of the rst detection time n are investigated, and compared with the corresponding classical rst passage problem. Dark states, Zeno physics, a quantum renewal equation, winding number for the rst return problem (work of A. Grunbaum et al.), total detection probability, detection time operators and time wave functions are discussed.
 H. Friedman, D. Kessler, and E. Barkai Quantum walks: the rst detected passage time problem Phys. Rev. E. 95, 032141 (2017). Editor's suggestion.
 F. Thiel, E. Barkai, and D. A. Kessler First detected arrival of a quantum walker on an in nite line Phys. Rev. Lett. 120, 040502 (2018).
Event Organizer: Prof. Sasha Gerber