Techniques for scaling trapped ion quantum information processors
University of Oxford, UK
Trapped ions represent one of the most promising systems for realising quantum computing, but scaling up from a few to many qubits whilst keeping good control remains a significant challenge. Following a modular approach, where relatively simple traps containing a few ions are connected together photonically, I report progress on both local and remote entangling operations to be used in a two node quantum network.
As such a network can be better utilised using two ion species in each node, I will discuss work towards generating local high fidelity mixed species entanglement. In our scheme we use a single pair of Raman beams from one laser to perform a gate between Ca and Sr ions, by exploiting the relative proximity of their transitions. The gate mechanism is independent of the qubit frequency, and requires a simpler experimental arrangement than is normally used for mixed species gates.
I will also show preliminary results demonstrating remote ion entanglement, by interfering and measuring photons emitted by an ion in each trap. Finally, I will report results on local fast entanglement generation, at and beyond the motional period of ions in the trap.