S. Brouard et al., PERFECT ABSORBERS FOR STATIONARY AND WAVEPACKET SCATTERING, Journal of physics. A, mathematical and general, 27(12), 1994, pp. 120000439-120000445
Complex potentials that absorb the incoming wave in a finite distance
without reflection or transmission are found by a simple inversion tec
hnique, both for stationary and wavepacket scattering in one dimension
.