Weak measurement combined with quantum delayed-choice experiment and implementation in optomechanical system

Weak measurement [1,19] combined with quantum delayed-choice experiment that use quantum beam splitter instead of the beam splitter give rise to a surprising amplification effect, i.e., counterintuitive negative amplification effect. We show that this effect is caused by the wave and particle behaviours of the system to be and can't be explained by a semiclassical wave theory, due to the entanglement of the system and the ancilla in quantum beam splitter. The amplification mechanism about wave-particle duality in quantum mechanics lead us to a scheme for implementation of weak measurement in optomechanical system

Quantum State Transfer Characterized by Mode Entanglement

We study the quantum state transfer (QST) of a class of tight-bonding Bloch electron systems with mirror symmetry by considering the mode entanglement. Some rigorous results are obtained to reveal the intrinsic relationship between the fidelity of QST and the mirror mode concurrence (MMC), which is defined to measure the mode entanglement with a certain spatial symmetry and is just the overlap of a proper wave function with its mirror image. A complementarity is discovered as the maximum fidelity is accompanied by a minimum of MMC. And at the instant, which is just half of the characteristic time required to accomplish a perfect QST, the MMC can reach its maximum value one. A large class of perfect QST models with a certain spectrum structure are discovered to support our analytical results.Comment: 6 pages, 3 figures. to appear in PR

Exploring the increasing role of the real estate sector in the Chinese economy : 1997-2002

The Chinese government launched a series of real estate reform policies in 1998, which further changed the real estate sector from socialist plan-oriented to modern marketoriented. This paper compares the role of the real estate sector in the Chinese economy in years 1997 and 2002 by using the recently published input-output OECD database. Results verify that the Chinese real estate sector played an increasing role in the Chinese economy with higher contributions and stronger push and pull power in 2002 than those in 1997. However, compared with other countries, especially for some OECD countries, the Chinese real estate sector has a relative lower contribution.<br /