School of Physics CM/AMO/GTRI Seminar - Dr. Peter Schwindt

In my talk, I will focus on two projects in our quantum sensing group at Sandia: the development of optically pumped (atomic) magnetometers (OPMs) for magnetoencephalography (MEG) and atomic clocks based on trapped ions. Over the past decade, OPMs have proven to be an exciting new to technology for MEG, the measurement and localization of neuronal currents in the human brain. OPMs can be placed close to the brain and can be worn offering new paradigms for MEG measurements for neuroscientists and clinicians.  Since 2007, my group at Sandia has been developing OPMs, performing some of the first demonstrations of MEG with compact OPM sensor heads. I will present various aspects of our development efforts. I will describe our first OPM-MEG system where we implemented a 24-channel OPM system inside a person-sized magnetic shield. With the system, we have been able to localize neuronal sources and decode MEG signals using machine learning techniques to determine perceived speech in a closed vocabulary experiment. I will also discuss our most recent effort to toward implementing a 108-channel optically pumped magnetometer (OPM) array in a magnetically shielded room.  

Second, I will discuss our efforts in furthering the development of highly miniaturized trapped Yb ion atomic clocks. Notably, we have two miniature ion trap vacuum packages that have been sealed for as long as 10 years with no active pumping. We find the lifetime of the ions within the trap has increased over time for both traps and can be as long as 50 days, and in operating the traps within a clock, we demonstrate a short-term fractional frequency instability of 5×10-13 at 1 s of integration.