Russian Microelectronics

Implementation of a Two-Qubit C-NOT Quantum Gate in a System of Two Double Quantum Dots, a Microcavity, and a Laser

Alexander V. Tsukanov, V. G. Chekmachev

Published Sep 1, 2018• 0 citations

Abstract

We study the possibility of implementing a two-qubit controlled-NOT gate operation in a structure consisting of two semiconductor double quantum dots placed in a high- Q optical microcavity and governed by a resonant laser field. The effect of relaxation processes on the dynamics of the two-electron system is discussed. The dissipation rates allowing quantum error correction algorithms to be used are determined. The existing additional excitation channel (laser pulse) is shown to weaken the effect of the nonideality of the cavity on the evolution of the states. Optimal electron coupling coefficients in the quantum dots with control fields are fitted, in which the controlled qubit is switched with the highest probability and the gate implementation takes several hundreds of picoseconds.

DOI: 10.1134/s1063739718050074

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