Experimental detection of Anderson localization of light in 3D vs 2D I have a question about the experimental realization of Anderson localization of light. I am a theorist, and have not worked much in optics, so please bear with me.
Anderson localization of light in 3D has a turbulent history. Notable experimental papers are

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*D. S. Wiersma, P. Bartolini, A. Lagendijk, and R. Righini, Localization of light in a disordered medium, Nature 390, 671 (1997).

*T. Sperling, W. B¨uhrer, C. M. Aegerter, and G. Maret, Direct determination of the transition to localization of light in three dimensions, Nature Photonics 7, 48 (2013).
where they use $\mathrm{GaAs}$ and $\mathrm{TiO}_2$ powders respectively.

However, both of these papers has been discussed/refuted by saying that the observed exponential suppression of the conductance could be attributed to absorption or fluorescence respectively. The current status of the field seems to be that 3D Anderson localization of light has not been observed.
On the other hand in 2D it seems that Anderson localization of light has been observed, for instance in

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*T.  Schwartz,  G.  Bartal,  S.  Fishman,  and  M.  Segev,Transport  and  Anderson  localization  in  disordered  two-dimensional photonic lattices, Nature446, 52 (2007).

*S. Karbasi, C. R. Mirr, P. G. Yarandi, R. J. Frazier, K. W. Koch, and A. Mafi, Observation of transverse anderson localization in an optical fiber, Opt. Lett.37, 2304(2012).

In the 2D experiments above they have not used powders, they have used SBN:60 and polysterene/PMMA fibers respectively.
The current status of the field seems to acknowledge that there has not been detected Anderson localization of light in 3D, only in 2D (and 1D).

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*T. Giordani, W. Schirmacher, G. Ruocco, and M. Leonetti, Transverse and quantum localization  of light: A review on theory and experiments, Frontiers in Physics 9, 439 (2021).

My question is why is absorption, fluorescence, etc... not an issue in the 2D systems experimentally, when it is an issue in the 3D systems?
Is it somehow related to that the investigated 3D materials are powders, and 2D systems are solids?
Any related comment/answer is highly appreciated!
 A: I think the answer was more simple than I anticipated. The point is that in to enable 3D Anderson localization of light, the strength of disorder must be larger than some critical value. This has limited the current search to materials with large refractive indexes, such as powdered GaAs, GaP, TiO2 etc, which all have exhibited absorption, fluorescence, and other non-linear effects. Simply put, there are not that many availabe candidates.
In lower dimensional systems (1D and 2D) Anderson localization is expected to occur regardless of the strength of disorder, there is no threshold value. This enables the search for Anderson localization in many more materials, without any need for an intrinsic large refractive index. Therefore one can use materials (such as glass) with small absorption, fluorescence, etc.
Simply put, in lower dimensions there are a lot of materials to choose from, in 3D there are few materials to choose from.
The situation may however be more subtle, so feel free to continue posting answers/comments.
