Liu Shuqi, Chen Yu, Jiang Jiatong, Wu Yuan, Guo Jinxian, Chen L Q
Opt Express. 2021 Oct 11;29(21):32865-32874. doi: 10.1364/OE.437535.
The measurement of intense E-field is a fundamental need in various research areas. An electro-optic (EO) sensor based on common path interferometer (CPI) is widely used due to its better temperature stability and controllability of optical bias. However, the small EO coefficient leads to poor sensitivity. In this paper, a quantum enhanced EO sensor is proposed by replacing the vacuum state in classical one with a squeezed-vacuum state. Theoretical analysis shows that the performance of the quantum enhanced EO sensor, including signal to noise ratio (SNR) and sensitivity, can always beat the classical one due to the noise suppression caused by the squeezed-vacuum state. Experimental results demonstrate that, there is still a 1.12dB quantum enhancement compared with the classical one when the degree of the squeezed-vacuum is 1.60dB. More importantly, except the increase of the EO coefficient or the optical power, the performance of the EO sensor can also be enhanced via quantum light source. Such a quantum enhanced EO sensor could be practically applied for the measurement of intense E-field.
强电场测量是各个研究领域的基本需求。基于共光路干涉仪（CPI）的电光（EO）传感器因其较好的温度稳定性和光学偏置可控性而被广泛应用。然而，小的电光系数导致灵敏度较差。本文提出了一种量子增强电光传感器，通过用压缩真空态取代经典传感器中的真空态。理论分析表明，由于压缩真空态引起的噪声抑制，量子增强电光传感器的性能，包括信噪比（SNR）和灵敏度，总是优于经典传感器。实验结果表明，当压缩真空度为1.60dB时，与经典传感器相比仍有1.12dB的量子增强。更重要的是，除了增加电光系数或光功率外，电光传感器的性能还可以通过量子光源得到增强。这种量子增强电光传感器可实际应用于强电场测量。
