Kramers-Kronig relations in laser intensity modulation method

In this short paper, the Kramers-Kronig relations for the laser intensity modulation method (LIMM) are presented to check the self-consistency of experimentally obtained complex current densities. The numerical procedure yields well defined, precise estimates for the real and the imaginary parts of the LIMM current density calculated from its imaginary and real parts, respectively. The procedure also determines an accurate high frequency real current value which appears to be an intrinsic material parameter similar to that of the dielectric permittivity at optical frequencies. Note that the problem considered here couples two different material properties, thermal and electrical; consequently, the validity of the Kramers-Kronig relation indicates that the problem is invariant and linear.