Speaker: Dr. Rui Li, Beijing Computational Science Research Center

Abstract: A spin-orbit qubit is a hybrid qubit that contains both orbital and spin degrees of freedom of an electron in a quantum dot. Here we study the exchange coupling between two spin-orbit qubits in a nanowire double quantum dot (DQD) with strong spin-orbit coupling (SOC). We find that while the total tunneling is irrelevant to the SOC, both the spin-conserved and spin-flipped tunnelings are SOC-dependent and can compete with each other in the strong SOC regime. Moreover, the Coulomb repulsion can combine with the SOC-dependent tunnelings to yield an anisotropic exchange coupling between the two spin-orbit qubits. Also, we give an explicit physical mechanism for this anisotropic exchange coupling.

Date&Time: December 20, 2013 (Friday), 14:30–15:30
Location: 606 Conference Room