Experimental study of Forrelation in nuclear spins

Correlation functions are often employed to quantify the relationships among interdependent variables or sets of data. Recently, a new class of correlation functions, called FORRELATION, has been introduced by Aaronson and Ambainis for studying the query complexity of quantum devices. It was found t...

Full description

Saved in:
Bibliographic Details
Published in:Science bulletin 2017-04, Vol.62 (7), p.497-502
Main Authors: Li, Hang, Gao, Xun, Xin, Tao, Yung, Man-Hong, Long, Guilu
Format: Article
Language:eng
Subjects:
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Correlation functions are often employed to quantify the relationships among interdependent variables or sets of data. Recently, a new class of correlation functions, called FORRELATION, has been introduced by Aaronson and Ambainis for studying the query complexity of quantum devices. It was found that there exists a quantum query algorithm solving 2-fold FORRELATION problems with an exponential quantum speedup over all possible classical means, which represents essentially the largest possible separation between quantum and classical query complexities. Here we report an experimental study probing the 2-fold and 3-fold FORRELATIONS encoded in nuclear spins. The major experimental challenge is to control the spin fluctuation to within a threshold value, which is achieved by developing a set of optimized GRAPE pulse sequences. Overall, our small-scale implementation indicates that the quantum query algorithm is capable of determining the values of FORRELATIONS within an acceptable accuracy required for demonstrating quantum supremacy, given the current technology and in the presence of experimental noise.
ISSN:2095-9273
2095-9281