Abstract: Faint states of light occur in multiple contexts, from fundamental physics to quantum information science to remote sensing and biology. At the same time, faint light naturally lends itself to optical quantum measurements. Such measurements not only enable detecting and using quantum properties of light such as entanglement and antibunching - but they also become a tool to observe and quantify quantum processes inside faint light sources.
In this talk, I will describe examples of optical quantum measurements. We will discuss a quantum state identification problem and its fundamental properties. We will see how this problem is intertwined with the theory of communications and how quantum measurements can be applied to enhance optical communication links and to benefit classical and quantum networks.
In the second half, I will cover measurements related to photon number statistics and correlations. It turns out that those measurements can identify different sources of light and measure underlying classical and non-classical dynamics that leads to or accompanies emission. Those measurements rely on detecting and quantifying emitted light only; thus, they are non-invasive. We will see several applications of this technique: from understanding single-photon emission in solid-state quantum dots to accurate counting single biomarkers and molecules in biologic settings.
JQI Seminars are held on Mondays during Fall and Spring semesters at 11:00 a.m. Eastern Time in Room 2400 of the Atlantic Building. University of Maryland affiliates may participate using Zoom. The seminars are also livestreamed on the JQI YouTube channel (https://www.youtube.com/user/JQInews), which supports audience participation in the chat interface.