Publication Date:
2016-10-28
Description:
Performing a quantum computation may seem complicated, but it can be done with a specially prepared beam of light and good photodetectors. On page 434 of this issue, Schwartz et al. (1) report on a prototype device that uses semiconductor quantum dots that generate long strings of photons in an entangled cluster state of light. Cluster states (2) carry a specific sort of entanglement—that is, the way in which the properties of different photons are correlated. In two dimensions—when the entangling connections form a net or lattice—cluster states become a universal resource; they can be used for all kinds of quantum information processing and are like a fuel for quantum computers. The entanglement can be realized between the polarizations of individual photons—the directions in which their individual electric field vectors point. A quantum calculation (3) can be run by measuring the polarization of each photon, one by one, in a specific order and direction, almost as simple as moving the beads of an abacus. Author: Hans J. Briegel
Keywords:
Quantum Physics
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
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Chemistry and Pharmacology
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Geosciences
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Computer Science
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Medicine
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Natural Sciences in General
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Physics
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