IoP - UvA Colloquium by John Bollinger (NIST, USA)
You are cordially invited to the Institute of Physics Colloquium on Thursday, 02 November 2023 given by prof. dr. John Bollinger of National Institute of Standards and Technology (NIST), USA. He will give a talk on Quantum dynamics and sensing with a 200-ion crystal stored in a Penning trap.
John Bollinger is a staff scientist and current group leader of the NIST Ion Storage Group in the Time and Frequency Division of the National Institute of Standards and Technology (NIST).
Abstract: Controlling the quantum dynamics of mesoscopic objects is of intrinsic as well as practical interest. I will describe experimental work implementing non-equilibrium quantum dynamics and sensing with laser cooled single-plane crystals of 200 ions stored in a Penning trap. With an optical dipole force we couple the center-of-mass vibrational mode of the ion crystal with the collective electronic spin (qubit) degree of freedom of the ions. This coupling can create entangled states of the ion crystal spin and center-of-mass motional degrees of freedom that can be used to engineer long-range quantum magnetic interactions between the ion spins.
In my talk I will focus on how spin-motion entangled states can also be used to sense weak motional excitations of the crystal center-of-mass mode. By controlling the coherent dynamics of the entangled state via a many-body echo, a weak motional excitation of the ion crystal is mapped into a spin rotation, which we measure. We demonstrate a sensitivity for measuring weak motional excitations of 8.8 ± 0.4 decibels below the standard quantum limit and a sensitivity for measuring electric fields of 240 ± 10 nanovolts per meter in 1 second . Feasible improvements should enable the use of trapped ions in searches for axion dark matter.
 Gilmore et al., Science 373, 673 (2021).
Drinks and snack will be served after the colloquium, outside of room C0.110.
All information can be found on the IoP website: https://iop.uva.nl/content/events/2023/11/colloquium-02-11.html?origin=YDX0oCAuRaWl9bnbtYhB4g
Secretariat Institute of Physics
R: C4.261a SP904
T: 020 525 5773