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Cancellation of Spin-Orbit Effects in Quantum Gates Based on the Exchange Coupling in Quantum Dots

Guido Burkard·Daniel Loss
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Abstract

We study the effect of the spin-orbit interaction on quantum gate operations based on the spin exchange coupling where the qubit is represented by the electron spin in a quantum dot or a similar nanostructure. Our main result is the exact cancellation of the spin-orbit effects in the sequence producing the quantum XOR gate for the ideal case where the pulse shapes of the exchange and spin-orbit interactions are identical. For the non-ideal case, the two pulse shapes can be made almost identical and the gate error is strongly suppressed by two small parameters, the spin-orbit constant and the deviation of the two pulse shapes. We show that the dipole-dipole interaction leads only to very small errors in the XOR gate.

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Guido Burkard, Daniel Loss. 2002-02-14. Cancellation of Spin-Orbit Effects in Quantum Gates Based on the Exchange Coupling in Quantum Dots. https://doi.org/10.1103/physrevlett.88.047903

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