摘要： Anderson localization (AL) of light, one of the most exotic mesoscopic phenomena, can be realized at two limits of disorder, namely, near-periodic disorder or strong disorder. AL can be characterized by sub-unity conductance. A critical parameter of interest is the fluctuations of conductance which reveals the statistical behaviour of the system and offers a more complete description of the underlying physics. However, the conventional technique of quantifying conductance precludes the measurement of the fluctuations thereof. In this work, we achieve Anderson localization of light in Gallium Arsenide membranes at both near-periodic disorder and strong disorder. We measure the generalized conductance fluctuations using the intensity distribution of light, and reveal hitherto unknown features of transport under the two approaches of localization. Figure 1 (a) and (b) depict the SEM images of ordered and strongly disordered structures. Fig. 1(c) shows the photonic mode formed due to the counter-propagating Bloch modes in the periodic system, and (d) shows the Anderson localized mode formed under strong disorder. Similar mode was also obtained at near-periodic disorder (not shown). The variance of the intensity distribution was used to compute the generalized conductance (cid:1859)′ = 4/3((cid:1874)(cid:1853)(cid:1870)((cid:1871)(cid:3028)(cid:3029)) ? 1), where (cid:1871)(cid:3028)(cid:3029) is the total transmission normalized to the ensemble average. The generalized conductance can be calculated for each configuration, so it facilitates a statistically consistent quantification. Fig. 1(e) shows the experimentally measured distribution of ln ((cid:1859)(cid:4593)) in the passband (black line) and in the stopband (red line). At weak/moderate disorder, the distributions are asymmetric, with long-tails at large ln((cid:1859)(cid:4593)). The passband modes are delocalized (ln((cid:1859)(cid:4593)) > 0), while the stopband modes show localization (ln((cid:1859)(cid:4593)) < 0). At strong disorder, the band-dependence is lost, and the ln((cid:1859)(cid:4593)) is seen to follow a normal distribution as expected. Clearly, at strong disorder, the entire distribution lies below zero, indicating localization of all modes, unlike in the weak/moderate disorder in the stopband, where a substantial number of modes are delocalized. This important difference in the localization physics is revealed by the statistical analysis of (cid:1859)(cid:4593).