High-Fidelity Ion State Detection Using Trap-Integrated Avalanche Photodiodes

Integrated technologies greatly enhance the prospects for practical quantum information processing and sensing devices based on trapped ions. High-speed and high-fidelity ion state readout is critical for any such application. Integrated detectors offer significant advantages for system portability and can also greatly facilitate parallel operations if a separate detector can be incorporated at each ion-trapping location. Here, we demonstrate ion quantum state detection at room temperature utilizing single-photon avalanche diodes (SPADs) integrated directly into the substrate of silicon ion trapping chips. We detect the state of a trapped Sr+ ion via fluorescence collection with the SPAD, achieving 99.92(1)% average fidelity in 450 Its, opening the door to the application of integrated state detection to quantum computing and sensing utilizing arrays of trapped ions.

Automated summary

This study demonstrates the utilization of single-photon avalanche diodes (SPADs) integrated into the substrate of silicon ion trapping chips for ion quantum state detection. It achieves a high fidelity and opens up new possibilities for quantum computing and sensing.