Towards single site addressing and detection in rotating crystals of ions in a Penning trap

We discuss plans for establishing programmable single qubit rotations on large, single-plane trapped-ion crystals (~200 ions) stored in a Penning ion trap.  These crystals rotate (rotation frequency ~180 kHz), making single site addressing challenging with focused laser beams.  Previous work has established global rotations of the ion qubits (or spins) and a global entangling gate generated by a spin-dependent force implemented with a moving 1D optical lattice.  We discuss how wave front deformations of the 1D optical lattice combined with a lattice frequency that is a multiple of the crystal rotation frequency can generate programmable ion qubit rotations without the need to rotate the lattice.  We will implement the wave front deformations with a deformable mirror (DM). Currently, we are characterizing a 137-actuator DM and preparing to add it to the trap’s optical system. In this first iteration we anticipate addressing small neighborhoods of ~6 ions occupying an area of 40 μm diameter.  We are also working on improving the detection of individual ions in the crystal with an imaging photon-counting camera that is capable of processing more than 10⁶ photon detection events/s.