Quantum optical interferometry via general photon-subtracted two-mode squeezed states

• 来源期刊: 中国物理B（英文版）
• 关键词: quantum optics phase sensitivity quantum metrology
• 年，卷（期）: 2019,（9）
• 页码范围: 280-287
• 页数: 8页
• 语种: 英文
• DOI: 10.1088/1674-1056/ab38a9

摘要

We investigate the sensitivity of phase estimation in a Mach-Zehnder interferometer with photon-subtracted two-mode squeezed vacuum states.Our results show that,for given initial squeezing parameter,both symmetric and asymmetric photon subtractions can further improve the quantum Cramér-Rao bound (i.e.,the ultimate phase sensitivity),especially for single-mode photon subtraction.On the other hand,the quantum Cramér-Rao bound can be reached by parity detection for symmetric photon-subtracted two-mode squeezed vacuum states at particular values of the phase shift,but it is not valid for asymmetric photon-subtracted two-mode squeezed vacuum states.In addition,compared with the two-mode squeezed vacuum state,the phase sensitivity via parity detection with asymmetric photon-subtracted two-mode squeezed vacuum states will be getting worse.Thus,parity detection may not always be the optimal detection scheme for nonclassical states of light when they are considered as the interferometer states.