An error exists in the above paper.

In [1], the equation \(k = \frac{1 - j}{{\sqrt {\frac{{\omega \mu_{0} }}{2}} }}\) (below equation 10) is wrong because the units of \(k\) are \({\rm m}^{1/2}\; \Omega^{ - 1/2}\) instead of \({\rm m}^{ - 1}\).