High-precision refractive index measurement has become a research hotspot in recent years.However,traditional refractive index measurement often adopts intensity detection,whose performance is restricted by the classi...High-precision refractive index measurement has become a research hotspot in recent years.However,traditional refractive index measurement often adopts intensity detection,whose performance is restricted by the classical detection limit and is thus hard to improve further.In order to break through this limitation,we propose a quantum-enhanced refractive index sensing scheme utilizing even-coherent-state sources in combination with parity detection.In this paper,we analyze the detection performance of the proposed system.Due to the inevitable photon loss in practical applications,the effects of photon loss on resolution and sensitivity are also investigated.Numerical results show that the resolution of the proposed strategy breaks through the Rayleigh limit and achieves super-resolving refractive index measurement.Relative to existing coherent-state schemes,our strategy leads to a twofold resolution improvement.Furthermore,the physical origins of the super-resolution are analyzed.展开更多
文摘High-precision refractive index measurement has become a research hotspot in recent years.However,traditional refractive index measurement often adopts intensity detection,whose performance is restricted by the classical detection limit and is thus hard to improve further.In order to break through this limitation,we propose a quantum-enhanced refractive index sensing scheme utilizing even-coherent-state sources in combination with parity detection.In this paper,we analyze the detection performance of the proposed system.Due to the inevitable photon loss in practical applications,the effects of photon loss on resolution and sensitivity are also investigated.Numerical results show that the resolution of the proposed strategy breaks through the Rayleigh limit and achieves super-resolving refractive index measurement.Relative to existing coherent-state schemes,our strategy leads to a twofold resolution improvement.Furthermore,the physical origins of the super-resolution are analyzed.
