Energy efficiency of quantum computers

TL;DR

This paper assesses the energy efficiency of various quantum computing platforms, compares them to classical computers, and proposes a framework for benchmarking future quantum architectures.

Contribution

It introduces a comprehensive framework for evaluating and comparing the energy efficiency of different quantum computing technologies.

Findings

Provides concrete estimates of energy consumption for current quantum platforms.

Analyzes advantages and disadvantages of each platform from an energy perspective.

Lays the groundwork for benchmarking future quantum computer energy efficiency.

Abstract

How much energy does a quantum computer consume? Are they more efficient than their classical counterparts? In this work, we make a step towards answering these questions. We define the energy efficiency of a quantum computer as the ratio of the number of algorithms it can perform during a given time over the energy consumed by the hardware during this time. We analyze the most representative physical platforms currently envisioned to be used as building blocks of quantum computers: superconducting qubits, silicon spin qubits, trapped ions, neutral atoms and photonic qubits. Including insights from experts in all these technologies and taking into account algorithm compilation constraints, we discuss the advantages and inconveniences of each platform from an energy standpoint. Beyond providing concrete values of the energy consumption of current quantum computers, we lay the foundation of a framework to benchmark the energy efficiency of any future quantum computing architecture.