Bell states of atoms with ultralong lifetimes and their tomographic state analysis -: art. no. 220402

被引：188

作者：

Roos, CF ^{[1
]}

Lancaster, GPT ^{[1
]}

Riebe, M ^{[1
]}

Häffner, H ^{[1
]}

Hänsel, W ^{[1
]}

Gulde, S ^{[1
]}

Becher, C ^{[1
]}

Eschner, J ^{[1
]}

Schmidt-Kaler, F ^{[1
]}

Blatt, R ^{[1
]}

机构：

[1] Univ Innsbruck, Inst Expt Phys, A-6020 Innsbruck, Austria

来源：

PHYSICAL REVIEW LETTERS | 2004年 / 92卷 / 22期

基金：

奥地利科学基金会;

关键词：

D O I：

10.1103/PhysRevLett.92.220402

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Arbitrary atomic Bell states with two trapped ions are generated in a deterministic and preprogrammed way. The resulting entanglement is quantitatively analyzed using various measures of entanglement. For this, we reconstruct the density matrix using single qubit rotations and subsequent measurements with near-unity detection efficiency. This procedure represents the basic building block for future process tomography of quantum computations. As a first application, the temporal decay of entanglement is investigated in detail. We observe ultralong lifetimes for the Bell states Psi(+/-), close to the fundamental limit set by the spontaneous emission from the metastable upper qubit level and longer than all reported values by 3 orders of magnitude.

引用

页码：220402 / 1

页数：4

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