Experimental observation of an anomalous weak value without post-selection

• 作者: AND GUANG-CAN GUO CHANG-LIANG REN CHUAN-FENG LI JIN-SHI XU MU YANG QIANG LI ZE-YAN HAO ZHENG-HAO LIU
• 来源期刊: 光子学研究:英文版
• 学科: 物理学
• 关键词: value SUBSET conveniently
• 年，卷（期）: 2020,（9）
• 页码范围: 1468-1474
• 页数: 7页
• 分类号: O41

摘要

Weak measurement has been shown to play important roles in the investigation of both fundamental and practical problems.Anomalous weak values are generally believed to be observed only when post-selection is performed,i.e.,only a particular subset of the data is considered.Here,we experimentally demonstrate that an anomalous weak value can be obtained without discarding any data by performing a sequential weak measurement on a single-qubit system.By controlling the blazing density of the hologram on a spatial light modulator,the measurement strength can be conveniently controlled.Such an anomalous phenomenon disappears when the measurement strength of the first observable becomes strong.Moreover,we find that the anomalous weak value cannot be observed without post-selection when the sequential measurement is performed on each of the components of a two-qubit system,which confirms that the observed anomalous weak value is based on sequential weak measurement of two noncommutative operators.