Experimental Realization of High-Efficiency Counterfactual Computation
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2015-08-21 |
| Journal | Physical Review Letters |
| Authors | Fei Kong, Chenyong Ju, Pu Huang, Pengfei Wang, Xi Kong |
| Institutions | CAS Key Laboratory of Urban Pollutant Conversion, University of Science and Technology of China |
| Citations | 20 |
Abstract
Section titled āAbstractāCounterfactual computation (CFC) exemplifies the fascinating quantum process by which the result of a computation may be learned without actually running the computer. In previous experimental studies, the counterfactual efficiency is limited to below 50%. Here we report an experimental realization of the generalized CFC protocol, in which the counterfactual efficiency can break the 50% limit and even approach unity in principle. The experiment is performed with the spins of a negatively charged nitrogen-vacancy color center in diamond. Taking advantage of the quantum Zeno effect, the computer can remain in the not-running subspace due to the frequent projection by the environment, while the computation result can be revealed by final detection. The counterfactual efficiency up to 85% has been demonstrated in our experiment, which opens the possibility of many exciting applications of CFC, such as high-efficiency quantum integration and imaging.