2013/02/28 by X. -D. Cai, Christian Weedbrook, Z. -E. Su +7 · 2 citations
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1103/physrevlett.110.230501
accepted version, to appear in Physical Review Letters
arxiv created 2013/06/03 · arxiv updated 2015/06/15
Solving linear systems of equations is ubiquitous in all areas of science and engineering. With rapidly growing data sets, such a task can be intractable for classical computers, as the best known classical algorithms require a time proportional to the number of variables N. A recently proposed quantum algorithm shows that quantum computers could solve linear systems in a time scale of order log(N), giving an exponential speedup over classical computers. Here we realize the simplest instance of this algorithm, solving 2*2 linear equations for various input vectors on a quantum computer. We use four quantum bits and four controlled logic gates to implement every subroutine required, demonstrating the working principle of this algorithm.