Matrix Isolation Research

Introduction

Atoms and molecules in vacuum have many scientific applications: the most accurate clocks, the most sensitive magnetometers, fundamental physics measurements, quantum computing, and quantum sensing. There are many difficulties associated with working with atoms in vacuum; for example, atoms move around and collide with each other. By cooling and trapping atoms and molecules in vacuum, these disadvantages can be reduced. Unfortunately, typical trapping methods limit atom numbers and densities to low values, which reduces their statistical sensitivity.

Instead, by implanting the atoms or molecules of interest inside a solid, atomic motion can be eliminated and much higher densities can be obtained. But implanting atoms in typical solids often destroys many of the favorable properties that make them interesting in the first place. 

In our work, we have shown that implanting atoms and molecules in very weakly-interacting cryogenic solids allows them to retain their important gas-phase properties for quantum sensing. 

Current research:
Single atoms in neon as quantum sensors

In our prior work, we have demonstrated that rubidium atoms trapped in solid neon have sufficient sensitivity to measure the magnetic field from a single nucleus. 

In ongoing work, we are developing techniques to move from working with ensembles to working with single atoms. This is the first step towards our long-term goals of  using a single atom as a quantum sensor to perform NMR and MRI measurements of a single molecule.

Current research:
Molecules in parahydrogen for fundamental physics measurements

Heavy polar molecules are extremely promising candidates for precision measurements of physics beyond the standard model, including tests of time-symmetry-violating physics. Inspired by the promising properties we have measured for atoms, we have begun work to measure the properties of heavy polar molecules implanted in solid parahydrogen. If these properties are favorable, we believe it will enable advancing the state-of-the-art of certain fundamental physics measurements by orders of magnitude.


Past results

Our first experiment successfully demonstrated optical pumping and detection of the electron spin of rubidium atoms implanted in a matrix of solid argon, but signal-to-noise was poor. We discovered more favorable behavior using cryogenic parahydrogen and neon as the host matrix.

We have trapped alkali-metal atoms at high densities, and demonstrated the ability to optically pump and measure their spin state with efficiencies comparable to other state-of-the art solid-state systems. The ensemble of atoms has very favorable properties: a long longitudinal relaxation time (T1), a long ensemble transverse relaxation time (T2*, also known as the dephasing time), and a long coherence time (T2).

These properties are very promising for quantum sensing of magnetic fields.

Selected publications: