Google’s secret plan for quantum computer supremacy

September 2, 2016

UCSB Martinis Group’s superconducting five-qubit array (credit: Erik Lucero)

Google* is developing a quantum computer that it believes will outperform the world’s top supercomputers, according to an August 31 New Scientist article and sourced to researchers contacted by the magazine.

Google’s ambitious goal is to achieve “quantum supremacy”— which would be achieved when “quantum devices without error correction can perform a well-defined computational task beyond the capabilities of state-of-the-art classical computers,” as the authors of an arXiv paper (open access) explain.

The task in this case: simulate the behavior of a random arrangement of quantum circuits in a 48-qubit grid, which would require 2.252 petabytes of memory, almost double that of the top supercomputer in the world.

To do that, Google plans to build a whopping 50 qubit computer. So far, Google has only announced a modest nine qubit computer, but it has hired arXiv paper co-author John M. Martinis at the University of California, Santa Barbara (see “Google partners with UC Santa Barbara team to build new superconductor-based quantum information processors” on KurzweilAI) to try.

Success may prepare Google to construct something even bigger: a fully scalable machine,” says Ian Walmsley at the University of Oxford.

* With partners NASA Ames, SGT, and University of California, Santa Barbara