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 in the DQD 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 between electrons 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.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 in the DQD 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 between electrons 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.

arXiv:1401.0101Physical Review BJul 10, 201417 citations

Spin-orbit coupling under control

Jesús González‐Vázquez, Ignacio R. Solá, Jesús Santamarı́a

Elsevier eBooksJan 1, 20060 citations

Spin Orbit Coupling in a Spin-1 System

Ryan Price, Daniel Campbell, Andika Putra +2 more

Bulletin of the American Physical SocietyJun 5, 20140 citations

Spin-orbit-coupling–induced resonance in an ultracold Bose gas

Qi Gu, Lan Yin

We study a two-component Bose gas with artificial spin-orbit coupling (SOC) which couples the center-of-mass momentum of an atom to its internal states. We show that in this system resonance can be induced by tuning SOC strength. With a two-dimensional SOC, resonances in two scattering channels can be induced by tuning the aspect ratio of SOC strengths. With a three-dimensional SOC, resonance in all three scattering channels can be induced by tuning the appropriate SOC strength. Our method can also be applied to a Fermi gas where resonance can also be induced with two- or three-dimensional SOC.We study a two-component Bose gas with artificial spin-orbit coupling (SOC) which couples the center-of-mass momentum of an atom to its internal states. We show that in this system resonance can be induced by tuning SOC strength. With a two-dimensional SOC, resonances in two scattering channels can be induced by tuning the aspect ratio of SOC strengths. With a three-dimensional SOC, resonance in all three scattering channels can be induced by tuning the appropriate SOC strength. Our method can also be applied to a Fermi gas where resonance can also be induced with two- or three-dimensional SOC.

arXiv:1802.06522Physical Review AJul 17, 20184 citations

Cavity-Assisted Spin Orbit Coupling

Chuanzhou Zhu, Lin Dong, Han Pu

Bulletin of the American Physical SocietyMar 16, 20160 citations

BCS-BEC crossover at finite temperature in spin-orbit-coupled Fermi gases

Lianyi He, Xu-Guang Huang, Hui Hu +1 more

By adopting a $T$ -matrix-based method within the ${G}_{0}G$ approximation for the pair susceptibility, we study the effects of the pairing fluctuation on the three-dimensional spin-orbit-coupled Fermi gases at finite temperature. The critical temperatures of the superfluid to normal phase transition are determined for three different types of spin-orbit coupling (SOC): (1) the extreme oblate (EO) or Rashba SOC, (2) the extreme prolate or equal Rashba-Dresselhaus SOC, and (3) the spherical (S) SOC. For EO- and S-type SOC, the SOC dependence of the critical temperature signals a crossover from BCS to BEC state; at strong SOC limit, the critical temperature recovers those of ideal BEC of rashbons. The pairing fluctuation induces a pseudogap in the fermionic excitation spectrum in both superfluid and normal phases. We find that, for EO- and S-type SOC, even at weak coupling, sufficiently strong SOC can induce sizable pseudogap. Our research suggests that the spin-orbit-coupled Fermi gases may open new means to the study of the pseudogap formation in fermionic systems.By adopting a $T$-matrix-based method within the ${G}_{0}G$ approximation for the pair susceptibility, we study the effects of the pairing fluctuation on the three-dimensional spin-orbit-coupled Fermi gases at finite temperature. The critical temperatures of the superfluid to normal phase transition are determined for three different types of spin-orbit coupling (SOC): (1) the extreme oblate (EO) or Rashba SOC, (2) the extreme prolate or equal Rashba-Dresselhaus SOC, and (3) the spherical (S) SOC. For EO- and S-type SOC, the SOC dependence of the critical temperature signals a crossover from BCS to BEC state; at strong SOC limit, the critical temperature recovers those of ideal BEC of rashbons. The pairing fluctuation induces a pseudogap in the fermionic excitation spectrum in both superfluid and normal phases. We find that, for EO- and S-type SOC, even at weak coupling, sufficiently strong SOC can induce sizable pseudogap. Our research suggests that the spin-orbit-coupled Fermi gases may open new means to the study of the pseudogap formation in fermionic systems.

arXiv:1303.4136Physical Review AMay 22, 201320 citations

By adopting a

T

-matrix-based method within the

{G}_{0}G

approximation for the pair susceptibility, we study the effects of the pairing fluctuation on the three-dimensional spin-orbit-coupled Fermi gases at finite temperature. The critical temperatures of the superfluid to normal phase transition are determined for three different types of spin-orbit coupling (SOC): (1) the extreme oblate (EO) or Rashba SOC, (2) the extreme prolate or equal Rashba-Dresselhaus SOC, and (3) the spherical (S) SOC. For EO- and S-type SOC, the SOC dependence of the critical temperature signals a crossover from BCS to BEC state; at strong SOC limit, the critical temperature recovers those of ideal BEC of rashbons. The pairing fluctuation induces a pseudogap in the fermionic excitation spectrum in both superfluid and normal phases. We find that, for EO- and S-type SOC, even at weak coupling, sufficiently strong SOC can induce sizable pseudogap. Our research suggests that the spin-orbit-coupled Fermi gases may open new means to the study of the pseudogap formation in fermionic systems.