An Operator Absorbing Boundary Condition for the Absorption of Electromagnetic Waves in Dispersive Media

An absorbing boundary condition (ABC) is presented for the absorption of electromagnetic waves in dispersive media in problems where the frequency bandwidth of interest is limited. The condition relies on an operator designed to absorb the waves in the considered bandwidth. Numerical experiments demonstrate the effectiveness of the operator in human body media. Due to its simple implementation, the operator ABC may be an alternative to the perfectly matched layer in applications where the bandwidth does not exceed one or two decades of frequency.