Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Building Quantum Computers

Published

Author(s)

Emanuel H. Knill

Abstract

In theory, quantum computers can be used to efficiently factor numbers, quadratically speed up many search and optimization problems, and enable currently impossible physics simulations. At first, quantum states appeared to be too fragile for implementing large quantum computers. Fortunately, because of theoretical advances in quantum error correction and fault tolerance, there are now no fundamental obstacles to realizing quantum computers. However, building quantum computers is difficult. Current experiments can barely achieve adequate control of two quantum bits. Nevertheless, the gap between theoretical and practical quantum computing is closing. In what follows, I give a brief explanation of what quantum computers are, explain why we believe that arbitrarily large quantum computations can be accurately implemented in principle, and survey the experimental state of the art and main implementation challenges.
Citation
IEEE Information Theory Society News Letter
Volume
58
Issue
4

Keywords

Quantum computers, quantum devices

Citation

Knill, E. (2008), Building Quantum Computers, IEEE Information Theory Society News Letter, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=900161 (Accessed March 3, 2024)
Created December 1, 2008, Updated February 19, 2017