Building a Stylus Trap and Deep Parabolic Mirror to Study and Control Quantum Jumps*

In this poster we present a method for studying quantum jumps in trapped barium ions using a stylus trap and deep parabolic mirror. This novel design minimizes the solid angle blocked by the trap electrodes allowing about 96% of the photons from the ion to hit the surrounding mirror when the ion sits at the focus of the mirror. This solid angle combined with the 90% reflectivity of the bare aluminum mirror, results in a total single photon collection efficiency of over 86%. High quantum efficiency single photon detectors, such as avalanche photodiodes or transition-edge detectors, will be used to maximize the overall photon detection efficiency necessary for the types of experiments we are planning.

We are constructing this system in two versions. The first version consists of just the stylus trap in the vacuum chamber without the mirror. This version is currently being used to trap barium ions and establish trapping parameters that will be used in version two. The second version will consist of a stylus trap with a steeper taper increasing the solid angle to 97.2% and resulting in a collection efficiency of 87.5%.

Part of the motivation for this research comes from work of Minev et al [1], whose group found they could predict, and even reverse, a quantum jump from ground state to an excited state of a superconducting artificial atom - a transmon qubit. Once our trap is complete, we plan on attempting to replicate these results.

[1] Minev, Z K et al. “To catch and reverse a quantum jump mid-flight.”