Integration of a low finesse optical cavity with a microfabricated surface ion trap

We present initial data on a new system in which a 37-mm long optical cavity is integrated coaxially with a silicon micro-fabricated surface electrode ion trap (Roadrunner, Sandia National Laboratories [1]), with the goal of scaling systems up to more ions for computation and simulation. The system makes use of broadband visible-spectrum HR-coated mirrors to create a medium-finesse optical cavity coupled to a chain of barium ions. We present data on cavity cooperativity and finesse across a range of wavelengths, as well as the characteristics of the new Roadrunner ion trap. This new system will allow us to explore several new schemes, including a fast, coherent, photonic interface between ion chains [2]. This may allow the entanglement of individual, spatially separated qubits within one single trap with rates above 10 kHz. Further scaling will be possible by using two-photon networking protocols, demonstrating cavity-enhanced photon collection from ensembles of ions, which could be used to connect multiple cavity-based modules. Finally, we explore the use of the cavity mode to form a blue-detuned optical lattice with 435 nm light to suppress the motion of ions along the axial direction. This may allow individual addressing and controlled spin-spin interactions in chains of up to a hundred ions, with applications to quantum simulation, including that of lattice gauge theories.

 

1. M. C. Revelle et al., The Roadrunner Trap (2023).

2. J. Ramette et al., PRX Quantum, 3, 010344 (2022).