Erratum: “The origin of non-Drude terahertz conductivity in nanomaterials” [Appl. Phys. Lett. 100, 132102 (2012)

Abstract

In a recent letter, we proposed a model for the nonDrude terahertz conductivity of nanosilicon and hexagonal Ge2Sb2Te5 (GST) based on a series sequence of two contributions: the conductivities of free carriers and tunneling carriers. The best fit of the proposed model to nanosilicon experimental data also used e1, where e1 is the background dielectric constant, as one of the parameters. As the experimental THz conductivity reported for nanosilicon has been obtained from optical-pumping THz spectroscopy (Ref. 7), the effect of e1 is subtracted from the experiment itself. Thus, we do not need to include the effect of e1 in fitting the model to experimental data. Figs. 1(a) and 1(b) show the corrected results of the real and imaginary part of conductivity in nanosilicon. Deduced physical parameters are also modified (f1⁄4 0.83, nf1⁄4 5.3 10 cm , s1⁄4 2.0 10 14 s, nt1⁄4 2.0 10 cm , and st1⁄4 2.0 10 14 s). Note that the results for GST are unaltered, because the experimental data are not obtained by optical-pumping. Finally, we should comment on the way in which we used Eq. (5) to calculate the overall conductivity. We described the tunneling conductivity as rt*(x)1⁄4 rtR(x) þ irtI(x) in Eq. (3). Since Eqs. (2) and (3) in the literature have been derived for e ixt and e, respectively, we had to change i to i in rt*(x) in the actual calculations in Eq. (5) to maintain consistency and causality. Also, Ref. 7 cited in the text in line 10, column 2 on page 2 should have been 9.