A Quantum von Neumann Architecture for Large-Scale Quantum Computing

TL;DR

This paper proposes a Quantum von Neumann architecture inspired by classical computer design principles, enabling scalable quantum computing with specialized hardware, exemplified by the Quantum 4004 model based on trapped ions.

Contribution

It introduces a novel quantum architecture framework that separates computation and storage, and demonstrates its implementation with a simplified, scalable trapped ion quantum computer model.

Findings

The Quantum 4004 can store 32,768 qubits in memory.

Single-qubit operations take 10 microseconds, two-qubit operations take 20 microseconds.

The architecture supports large-scale quantum computation with multiplexing and pipelining.

Abstract

As the size of quantum systems becomes bigger, more complicated hardware is required to control these systems. In order to reduce the complexity, I discuss the amount of parallelism required for a fault-tolerant quantum computer and what computation speed can be achieved in different architectures. To build a large-scale quantum computer, one can use architectural principles, from classical computer architecture, like multiplexing or pipelining. In this document, a Quantum von Neumann architecture is introduced which uses specialized hardware for the different tasks of a quantum computer, like computation or storage. Furthermore, it requires long qubit coherence and the capability to move quantum information between the different parts of the quantum computer. As an example, a Quantum von Neumann architecture for trapped ions is presented which incorporates multiplexing in the memory region for large-scale quantum computation. To illustrate the capability of this architecture, a model trapped ion quantum computer based on Quantum von Neumann architecture, the Quantum 4004, is introduced. Its hardware is optimized for simplicity and uses the classical Intel 4004 CPU from 1971 as a blueprint. The Quantum 4004 has only a single processing zone and is structured in 4 qubit packages. Its quantum memory can store up to 32768 qubit ions and its computation speed is 10 $\mu$s for single qubit operations and 20 $\mu$s for two-qubit operations.