Towards quantum control and spectroscopy of a single hydrogen molecular ion

The complexity and variety of molecules offer opportunities for metrology and quantum information that go beyond what is possible with atomic systems. The hydrogen molecular ion is the simplest of all molecules and can thus be calculated ab initio to very high precision. Combined with spectroscopy this allows to determine fundamental constants and test fundamental theory at record precision. Spectroscopy should improve substantially by performing experiments with single H2+ ions, reducing systematic uncertainties and improving signal strength. This necessitates quantum control.

I will present our progress towards full quantum control of a single H2+ ion. Our most recent results demonstrate the co-trapping and cooling of single H2+ and 9Be+ ions. The experimental apparatus features a cryogenic ultra-high vacuum chamber, housing a micro-fabricated monolithic linear Paul trap. H2+ is loaded into the trap by electron bombardment of H2. We observe trapping times in excess of 8 hours. We aim to use He buffer gas cooling in combination with quantum logic spectroscopy to initialize the internal state of H2+ in a pure quantum state and implement non-destructive readout.