Ahh yes NLM with unstable materials as evidenced by publications from Polariton, KIT, Eindhoven, and others saying so. These same publications praise Perkinamine stability.
NLM’s most stable material requires an additional step AFTER poling to maintain its stability and even so, suffers serious degradation in performance after 2,000 hours.
Oh and NLM has basically no patents. They did patent their cross-linked material.
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