Enhancement of entanglement by means of squeezing in continuous-variable systems

• Main Author: Er, Chern Han
• Other Authors: Chew Lock Yue
• Format: Final Year Project
• Language: English
• Published: 2010
• Subjects: DRNTU::Science::Physics::Atomic physics::Quantum theory
• Online Access: http://hdl.handle.net/10356/40829
• Institution: Nanyang Technological University

In this project, we investigate the enhancement of entanglement by means of local squeezing of the coherent initial state in various two-mode coupled harmonic oscillator systems within the pure Gaussian regime. Remarkably, we discover that the enhancement of maximum entanglement produced in the time evolution occurs under two different conditions: the existence or non-existence of an entanglement enhancement threshold. By developing a mathematical framework, we are able to: (i) develop a phase-space picture that allows us to explain the entanglement enhancement due to squeezing; (ii) explain the origin of the threshold. In particular, it has enabled us to determine the analytical expression of the threshold.