Quantum Parallelism in Quantum Information Processing (original) (raw)

NASA/ADS

Abstract

We investigate distinguishability (measured by fidelity) of the initial and the final state of a qubit, which is an object of the so-called nonideal quantum measurement of the first kind. We show that the fidelity of a nonideal measurement can be greater than the fidelity of the corresponding ideal measurement. This result is somewhat counterintuitive, and can be traced back to the quantum parallelism in quantum operations, in analogy with the quantum parallelism manifested in the quantum computing theory. In particular, while the quantum parallelism in quantum computing underlies efficient quantum algorithms, the quantum parallelism in quantum information theory underlies this, classically unexpected, increase of the fidelity.

Publication:

arXiv e-prints

Pub Date:

December 2002

DOI:

10.48550/arXiv.quant-ph/0212129

arXiv:

arXiv:quant-ph/0212129

Bibcode:

2002quant.ph.12129D

Keywords:

E-Print:

13 pages, 1 color figure, uses tole2.sty, psfig.tex