Optimal Copying of One Quantum Bit

Details Optimal Copying of One Quantum Bit Optimal Copying of One Quantum Bit

1998-05-22

arxiv.org/abs/quant-ph/9805073v1

Phys.Rev. A58 (1998) 4377-4393

Physics

Quantum Physics

RevTex, 26 pages, 2 Postscript figures

Scientific paper

10.1103/PhysRevA.58.4377

A quantum copying machine producing two (in general non-identical) copies of an arbitrary input state of a two-dimensional Hilbert space (qubit) is studied using a quality measure based on distinguishability of states, rather than fidelity. The problem of producing optimal copies is investigated with the help of a Bloch sphere representation, and shown to have a well-defined solution, including cases in which the two copies have unequal quality, or the quality depends upon the input state (is ``anisotropic'' in Bloch sphere language), or both. A simple quantum circuit yields the optimal copying machine. With a suitable choice of parameters it becomes an optimal eavesdropping machine for some versions of quantum cryptography, or reproduces the Buzek and Hillery result for isotropic copies.

Affiliated with

Also associated with

No associations

Rating

Optimal Copying of One Quantum Bit does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Optimal Copying of One Quantum Bit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optimal Copying of One Quantum Bit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-561171