Optimal scheme for estimating a pure qubit state via local measurements -: art. no. 277904

被引：34

作者：

Bagan, E ^{[1
]}

Baig, M ^{[1
]}

Muñoz-Tapia, R ^{[1
]}

机构：

[1] Univ Autonoma Barcelona, Fac Ciencias, Grp Fis Teor & IFAE, E-08193 Barcelona, Spain

来源：

PHYSICAL REVIEW LETTERS | 2002年 / 89卷 / 27期

关键词：

D O I：

10.1103/PhysRevLett.89.277904

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We present the optimal scheme for estimating a pure qubit state by means of local measurements on N identical copies. We give explicit examples for low N. For large N, we show that the fidelity saturates the collective measurement bound up to order 1/N. When the signal state lays on a meridian of the Bloch sphere, we show that this can be achieved without classical communication.

引用

页码：277904 / 277904

页数：4

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