Entangled macroscopic quantum states in two superconducting qubits

被引：398

作者：

Berkley, AJ ^{[1
]}

Xu, H ^{[1
]}

Ramos, RC ^{[1
]}

Gubrud, MA ^{[1
]}

Strauch, FW ^{[1
]}

Johnson, PR ^{[1
]}

Anderson, JR ^{[1
]}

Dragt, AJ ^{[1
]}

Lobb, CJ ^{[1
]}

Wellstood, FC ^{[1
]}

机构：

[1] Univ Maryland, Ctr Superconduct Res, Dept Phys, College Pk, MD 20742 USA

来源：

SCIENCE | 2003年 / 300卷 / 5625期

关键词：

D O I：

10.1126/science.1084528

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

We present spectroscopic evidence for the creation of entangled macroscopic quantum states in two current-biased Josephson-junction qubits coupled by a capacitor. The individual junction bias currents are used to control the interaction between the qubits by tuning the energy level spacings of the junctions in and out of resonance with each other. Microwave spectroscopy in the 4 to 6 gigahertz range at 20 millikelvin reveals energy levels that agree well with theoretical results for entangled states. The single qubits are spatially separate, and the entangled states extend over the 0.7-millimeter distance between the two qubits.

引用

页码：1548 / 1550

页数：3

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