An Experimental Microarchitecture for a Superconducting Quantum Processor

TL;DR

This paper introduces a novel microarchitecture for superconducting quantum processors that enables precise control of quantum operations through a flexible, microcoded control scheme, bridging the gap between high-level programming and hardware execution.

Contribution

It presents a new control microarchitecture with microinstructions for superconducting quantum processors, enhancing the integration of quantum algorithms with hardware control.

Findings

Successfully demonstrated a gate-characterization experiment on a transmon qubit.

Developed a flexible, microcoded control scheme for quantum operations.

Enabled precise timing and control of quantum operations.

Abstract

Quantum computers promise to solve certain problems that are intractable for classical computers, such as factoring large numbers and simulating quantum systems. To date, research in quantum computer engineering has focused primarily at opposite ends of the required system stack: devising high-level programming languages and compilers to describe and optimize quantum algorithms, and building reliable low-level quantum hardware. Relatively little attention has been given to using the compiler output to fully control the operations on experimental quantum processors. Bridging this gap, we propose and build a prototype of a flexible control microarchitecture supporting quantum-classical mixed code for a superconducting quantum processor. The microarchitecture is based on three core elements: (i) a codeword-based event control scheme, (ii) queue-based precise event timing control, and (iii) a flexible multilevel instruction decoding mechanism for control. We design a set of quantum microinstructions that allows flexible control of quantum operations with precise timing. We demonstrate the microarchitecture and microinstruction set by performing a standard gate-characterization experiment on a transmon qubit.