Experimental methods cryogenic cooling

This author does not know of any application where just the dichroism or the dichroism and mechanical properties are measured dynamically, similar to the dynamic X-ray or birefringence experiments. This is probably due to the experimental difficulty. Specifically one would need a fairly high speed detector which generally requires cryogenic cooling and is fairly costly. Secondly, the sensitivity of the dichroism method is not considered to be better than a few percent. Since only small dynamic strains are involved in such an oscillatory experiment, the sensitivity required must be better than this. This latter problem could probably be overcome by time averaging. 

---