Circuit and System-Level Considerations Towards Scalable Trapped Ion Quantum Computer

This talk discusses in a systematic way the challenges and system-level aspects related to integrated circuits for miniaturization of a trapped ion quantum computer. First, system level aspects and physics review of a trapped ion quantum computer operation is given. Particularly, near-field microwave quantum logic is described in detail (on example of Be+, Ca+ and Yb+ ions). Various parts of the system are presented including microwave power amplifiers with envelope shaping along with integrated direct digital synthesizers (DDS) to drive Mølmer-Sørensen gates or high-speed DACs controlling the shuttling motion of the ions to the registers on the chip. The current state-of-the-art electronic realization is shown using off-the-shelf equipment. Next, the potential of miniaturization and scalability of the trapped ion quantum computer by means of integration is visualized. The required system-on-chip is described in detail and specified to building blocks. The challenges related to achieving the electrical specifications (such as suppression of unwanted harmonics or port isolation) are discussed. Modeling results at cryogenic temperature of SiGe HBT and MOS transistors of 0.13µm SiGe HBT BiCMOS technology are presented. The results of modeling are applied to design of the microwave sources for controlling the qubit states. Finally, a fully integrated system-on-chip for controlling the state of trapped ions is discussed.