pak's Blog

Opt. Express, Vol. 17, No. 17. (17 August 2009), pp. 15170-15172.

As an author on the replied-to Comment, I'd like to make a couple of observations on this Reply. Unfortunately the Optics Express "comment" process uses only independent referees, not the other authors; so we did not get the chance to adapt our Comment accordingly.

1) LOSS

For the ExB continuity equation, the work done is E.J=E.dt P + E.curl M, i.e. it is all in terms of electric current.

For the ExH continuity equation, the work done is E.dt P + H.dt M, ie it has an electric current part (E.dt P = E.J_P) and a magnetic current part(H.dt M = H.K_M).

Markel's "no other channel" (p.2 para.3) exists, and is H.dt M; the work done on the ficticious magnetic monopole current representing the magnetization M.

For more details see "Four Poynting Theorems" Eur. J. Phys. 30, 983 (2009); http://www.citeulike.org/user/pak/article/5044532

I regret that we did not make this clear in our original Comment.

2) NPV conditions

In Markel's discussion of the Im(epsilon mu) NPV condition, he does not distinguish between doubly passive and mixed active-passive cases with net loss, or between doubly active cases and mixed active-passive cases with net gain. However, he should do so, because the NPV condition for mixed active-passive media is _not_ Im(epsilon mu).

For more details see "Criteria for negative refraction in active and passive media", P. Kinsler, M. W. McCall, Microwave Opt. Tech. Lett. 50, 1804 (2008); http://www.citeulike.org/user/pak/article/2988946