Spectral Maximum in the Terahertz Photoconductance of a Quantum Point Contact

The disappearance of the giant terahertz photoconductance of a quantum point contact under the increase in the photon energy, which was discovered experimentally (Otteneder et al., Phys. Rev. Appl. 10 , 014015 (2018)) and studied by the numerical calculations of the photon-stimulated transport (O. A. Tkachenko et al., JETP Lett. 108 , 396 (2018)), is explained by the momentum conservation upon absorption of photons by tunneling electrons and on the base of perturbation theory calculations.