| Original Articles |
|
|
|
|
Quantum Generalized Subspace Projector Measurement and Measurement Induced Entanglement |
| ZHANG Ming1;DONG Guo-Hua1;DAI Hong-Yi2;HU De-Wen1 |
| 1College of Mechatronics and Automation, National University of Defense Technology, Changsha 410073
2College of Science, National University of Defense Technology, Changsha 410073 |
|
| Cite this article: |
|
ZHANG Ming, DONG Guo-Hua, DAI Hong-Yi et al 2006 Chin. Phys. Lett. 23 1072-1075 |
|
|
|
|
Abstract We propose the concept of the quantum generalized subspace projector measurement (QGSPM). The distinguished properties of QGSPM is revealed: no matter what the state of the system is prior to the measurement and what the measured result occurs, the state posterior to the measurement can be collapsed onto the specified subspace. Subsequently, the quantum generalized case-projector measurement (QGCPM), as a special case of QGSPM, is also discussed carefully. It is demonstrated that no matter what measured result occurs, the state of the system posterior to QGCPM can be collapsed into one of pure states. Consequently, QGCPM can be used to generate the maximally entangled pure states for multiple particles. As illustrative examples, several concrete methods of generating entanglement are proposed for two two-level particles. It is found that the maximally entangled pure states of two 2-level particles can be generated just by a single QGCPM and the corresponding QGCPM operators are physically realizable in principle if an ancillary four-dimensional quantum system can be introduced.
|
| Keywords:
03.65.Ta
03.67.Mn
|
|
|
Published: 01 May 2006
|
|
| PACS: |
03.65.Ta
|
(Foundations of quantum mechanics; measurement theory)
|
| |
03.67.Mn
|
(Entanglement measures, witnesses, and other characterizations)
|
|
|
|
|
|
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
