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Ma Luo

Publications and source records attributed to Ma Luo.

43 records · Page 3Linked to original sources
arXiv2018

Topological zero-line mode of bilayer graphene with Rashba spin-orbital coupling and staggered sublattice potentials

Domain wall in bilayer graphene with Rashba spin-orbital coupling and staggered sublattice potentials, at the interface between two domains with different gated voltages, is studied. Varying type of zero-line modes are identified, including zero-line mode with pure spin filtering effect. The Y-shape current partition at the junction among three different domains are proposed.

cond-mat.mes-hall↗
arXiv2016

Large photon drag effect of intrinsic graphene induced by plasmonic evanescent field

Large photon drag effect of the massless Dirac Fermions in intrinsic graphene is predicted for a graphene-on-plasmonic-layer system. The surface plasmons in the plasmonic layer enlarge the wave number of photon for hundreds of time of that in vacuum. The evanescent field of the surface plasmons generates directional motion of carriers in the intrinsic graphene, because of the large momentum transfer from the surface plasmon to the excited carriers. A model Hamiltonian is developed on the assumption that the in-plane wavelength of the surface plasmons is much smaller than the mean free path of the carriers. The time evolution of density matrix is solved by perturbation method as well as numerical integration. The non-diagonal density matrix elements with momentum transfer lead to gauge current that is the optically driven macroscopic direct current. The dependence of the macroscopic direct current on the incident direction and intensity of the laser field is studied.

cond-mat.mes-hall↗
arXiv2009

Modification of spin mixing of spinor BEC by cavity QED coupling

Dressed states of spinor Bose-Einstein condensates of spin-1 atoms coupling with optical cavity modes with far off resonance frequency are investigated. The exact solution of time evolution of population of spin component is derived, and the numerical result shows that the evolution is different from spin mixing without the coupling. Due to the coupling with the atoms, the photon state also evolute to different optical cavity modes.

physics.atm-clus↗
arXiv2008

Interference of the evolutions of Rb and Na Bose-Einstein condensates

Spin evolution of a mixture of two species of spin-1 Bose-Einstein condensates (Rb and Na) has been investigated beyond the mean field theory. Both analytical expression and numerical results on the populations of spin-components are obtained. The interference is found to depend on the initial states and the inter-species interaction sensitively. A number of phenomena arising from the interference have been predicted. In particular, periodic behavior and the alternate appearances of a zone of oscillation and a long quiet zone are found.

physics.atm-clus↗
arXiv2007

Spin evolution of spin-1 Bose-Einstein condensates

An analytical formula is obtained to describe the evolution of the average populations of spin components of spin-1 atomic gases. The formula is derived from the exact time-dependent solution of the Hamiltonian $H_{S}=c mathbf{S}^{2}$ without using approximation. Therefore it goes beyond the mean field theory and provides a general, accurate, and complete description for the whole process of non-dissipative evolution starting from various initial states. The numerical results directly given by the formula coincide qualitatively well with existing experimental data, and also with other theoretical results from solving dynamic differential equations. For some special cases of initial state, instead of undergoing strong oscillation as found previously, the evolution is found to go on very steadily in a very long duration.

physics.atm-clus↗
arXiv2000

Nuclear dependence asymmetries in direct photon production

We study the nuclear dependences of high-$p_T$ jet cross sections in one photon and one jet production in proton-nucleus collisions. We find that there exist asymmetries between the outgoing jets and photons. A convincing reason responsible for those asymmetries are demonstrated in perturbative QCD. Significant nuclear enhancements are also found in the inclusive jet cross sections.

hep-ph↗