In this paper, a method to measure the tiny spin splitting of the spin Hall effect of light (SHEL) using the almost-balanced weak measurement (ABWM) is presented. The ABWM technique uses two orthogonal post-selected states to record all of the information, which is a precise measurement method being different from the standard weak measurement (SWM). The theory model to describe the SHEL measurement based on ABWM is established. As results, the ABWM scheme has a larger amplification factor, reaching ∼10⁵, which is nearly one order of magnitude higher than that of the SWM. When the post-selected angle is less than a certain value, the sensitivity and amplification factor of the ABWM scheme are higher than those of the SWM scheme, while the measurement precision and SNR of the ABWM technique are comparable to those of the SWM scheme. This research may have great potential for the precision metrology or sensing field based on the SHEL measurement.

中文翻译：

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几乎平衡的弱测量中的异常放大，用于测量光的自旋霍尔效应

本文提出了一种使用几乎平衡的弱测量（ABWM）来测量光的自旋霍尔效应（SHEL）的微小自旋分裂的方法。ABWM技术使用两个正交的后选择状态来记录所有信息，这是一种不同于标准弱测量（SWM）的精确测量方法。建立了描述基于ABWM的SHEL测量的理论模型。结果，ABWM方案具有较大的放大系数，达到约^{10 5}，比SWM高出近一个数量级。当后选角度小于特定值时，ABWM方案的灵敏度和放大系数高于SWM方案，而ABWM技术的测量精度和SNR与SWM方案相当。这项研究对于基于SHEL测量的精密计量学或传感领域可能具有巨大的潜力。