Active modulation of refractive index by stress in the terahertz frequency range: erratum

A previous paper [Appl. Opt.52, 6364 (2013)APOPAI0003-693510.1364/AO.52.006364] presented experimental work on the stress-optical effect in the terahertz frequency range. Although the theoretical model of experimental measurement is correct, there are two errors in the original version. As a result, the presented experimentally measured value of the refractive index-stress coefficient A of polytetrafluoroethylene (PTFE) is erroneous. This erratum points out the errors in the original paper and reports the correct values.