The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
John M Doyle - One of the best experts on this subject based on the ideXlab platform.
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large Spin Relaxation rates in trapped submerged shell atoms
Physical Review A, 2010Co-Authors: Colin B Connolly, Charles S Doret, Wolfgang Ketterle, John M DoyleAbstract:Spin Relaxation due to atom--atom collisions is measured for magnetically trapped erbium and thulium atoms at a temperature near 500 mK. The rate constants for Er--Er and Tm--Tm collisions are $3.0\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}$ and $1.1\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}$ cm${}^{3}$ ${\mathrm{s}}^{\ensuremath{-}1}$, respectively, $2--3$ orders of magnitude larger than those observed for highly magnetic $S$-state atoms. This is strong evidence for an additional, dominant, Spin Relaxation mechanism, electronic interaction anisotropy, in collisions between these ``submerged-shell,'' $L\ensuremath{\ne}0$ atoms. These large Spin Relaxation rates imply that evaporative cooling of these atoms in a magnetic trap will be highly inefficient.
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large Spin Relaxation rates in trapped submerged shell atoms
APS, 2010Co-Authors: Colin B Connolly, Charles S Doret, Wolfgang Ketterle, John M DoyleAbstract:Spin Relaxation due to atom–atom collisions is measured for magnetically trapped erbium and thulium atoms at a temperature near 500 mK. The rate constants for Er–Er and Tm–Tm collisions are 3.0 × 10 10 cm 3 s 1 and 1.1 × 10 10 cm 3 s 1 , respectively, 2–3 orders of magnitude larger than those observed for highly magnetic S-state atoms. This is strong evidence for an additional, dominant, Spin Relaxation mechanism, electrostatic anisotropy, in collisions between these “submerged-shell” L 6 0 atoms. These large Spin Relaxation rates imply that evaporative cooling of these atoms in a magnetic trap will be highly inefficient.
Sergio O Valenzuela - One of the best experts on this subject based on the ideXlab platform.
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strongly anisotropic Spin Relaxation in graphene transition metal dichalcogenide heterostructures at room temperature
Nature Physics, 2018Co-Authors: Antonio L Benitez, J F Sierra, Williams Savero Torres, Alois Arrighi, F Bonell, Marius V Costache, Sergio O ValenzuelaAbstract:A large enhancement in the Spin–orbit coupling of graphene has been predicted when interfacing it with semiconducting transition metal dichalcogenides. Signatures of such an enhancement have been reported, but the nature of the Spin Relaxation in these systems remains unknown. Here, we unambiguously demonstrate anisotropic Spin dynamics in bilayer heterostructures comprising graphene and tungsten or molybdenum disulphide (WS2, MoS2). We observe that the Spin lifetime varies over one order of magnitude depending on the Spin orientation, being largest when the Spins point out of the graphene plane. This indicates that the strong Spin–valley coupling in the transition metal dichalcogenide is imprinted in the bilayer and felt by the propagating Spins. These findings provide a rich platform to explore coupled Spin–valley phenomena and offer novel Spin manipulation strategies based on Spin Relaxation anisotropy in two-dimensional materials. Large Spin–orbit coupling can be induced when graphene interfaces with semiconducting transition metal dichalcogenides, leading to strongly anisotropic Spin dynamics. As a result, orientation-dependent Spin Relaxation is observed.
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strongly anisotropic Spin Relaxation in graphene transition metal dichalcogenide heterostructures at room temperature
arXiv: Mesoscale and Nanoscale Physics, 2017Co-Authors: Luis A Benitez, J F Sierra, Williams Savero Torres, Alois Arrighi, F Bonell, Marius V Costache, Sergio O ValenzuelaAbstract:Graphene has emerged as the foremost material for future two-dimensional Spintronics due to its tuneable electronic properties. In graphene, Spin information can be transported over long distances and, in principle, be manipulated by using magnetic correlations or large Spin-orbit coupling (SOC) induced by proximity effects. In particular, a dramatic SOC enhancement has been predicted when interfacing graphene with a semiconducting transition metal dechalcogenide, such as tungsten disulphide (WS$_2$). Signatures of such an enhancement have recently been reported but the nature of the Spin Relaxation in these systems remains unknown. Here, we unambiguously demonstrate anisotropic Spin dynamics in bilayer heterostructures comprising graphene and WS$_2$. By using out-of-plane Spin precession, we show that the Spin lifetime is largest when the Spins point out of the graphene plane. Moreover, we observe that the Spin lifetime varies over one order of magnitude depending on the Spin orientation, indicating that the strong Spin-valley coupling in WS$_2$ is imprinted in the bilayer and felt by the propagating Spins. These findings provide a rich platform to explore coupled Spin-valley phenomena and offer novel Spin manipulation strategies based on Spin Relaxation anisotropy in two-dimensional materials.
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pseudoSpin driven Spin Relaxation mechanism in graphene
Nature Physics, 2014Co-Authors: Dinh Van Tuan, Frank Ortmann, David Soriano, Sergio O Valenzuela, Stephan RocheAbstract:The prospect of transporting Spin information over long distances in graphene, possible because of its small intrinsic Spin–orbit coupling (SOC) and vanishing hyperfine interaction, has stimulated intense research exploring Spintronics applications. However, measured Spin Relaxation times are orders of magnitude smaller than initially predicted, while the main physical process for Spin dephasing and its charge-density and disorder dependences remain unconvincingly described by conventional mechanisms. Here, we unravel a Spin Relaxation mechanism for non-magnetic samples that follows from an entanglement between Spin and pseudoSpin driven by random SOC, unique to graphene. The mixing between Spin and pseudoSpin-related Berry’s phases results in fast Spin dephasing even when approaching the ballistic limit, with increasing Relaxation times away from the Dirac point, as observed experimentally. The SOC can be caused by adatoms, ripples or even the substrate, suggesting novel Spin manipulation strategies based on the pseudoSpin degree of freedom. Spin Relaxation in graphene is much faster than theoretically expected. Now, a scenario based on a mixing of Spin and pseudoSpin degrees of freedom and defect-induced spatial Spin–orbit coupling variations predicts longer Spin Relaxation times.
Antonio L Benitez - One of the best experts on this subject based on the ideXlab platform.
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strongly anisotropic Spin Relaxation in graphene transition metal dichalcogenide heterostructures at room temperature
Nature Physics, 2018Co-Authors: Antonio L Benitez, J F Sierra, Williams Savero Torres, Alois Arrighi, F Bonell, Marius V Costache, Sergio O ValenzuelaAbstract:A large enhancement in the Spin–orbit coupling of graphene has been predicted when interfacing it with semiconducting transition metal dichalcogenides. Signatures of such an enhancement have been reported, but the nature of the Spin Relaxation in these systems remains unknown. Here, we unambiguously demonstrate anisotropic Spin dynamics in bilayer heterostructures comprising graphene and tungsten or molybdenum disulphide (WS2, MoS2). We observe that the Spin lifetime varies over one order of magnitude depending on the Spin orientation, being largest when the Spins point out of the graphene plane. This indicates that the strong Spin–valley coupling in the transition metal dichalcogenide is imprinted in the bilayer and felt by the propagating Spins. These findings provide a rich platform to explore coupled Spin–valley phenomena and offer novel Spin manipulation strategies based on Spin Relaxation anisotropy in two-dimensional materials. Large Spin–orbit coupling can be induced when graphene interfaces with semiconducting transition metal dichalcogenides, leading to strongly anisotropic Spin dynamics. As a result, orientation-dependent Spin Relaxation is observed.
Colin B Connolly - One of the best experts on this subject based on the ideXlab platform.
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large Spin Relaxation rates in trapped submerged shell atoms
Physical Review A, 2010Co-Authors: Colin B Connolly, Charles S Doret, Wolfgang Ketterle, John M DoyleAbstract:Spin Relaxation due to atom--atom collisions is measured for magnetically trapped erbium and thulium atoms at a temperature near 500 mK. The rate constants for Er--Er and Tm--Tm collisions are $3.0\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}$ and $1.1\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}$ cm${}^{3}$ ${\mathrm{s}}^{\ensuremath{-}1}$, respectively, $2--3$ orders of magnitude larger than those observed for highly magnetic $S$-state atoms. This is strong evidence for an additional, dominant, Spin Relaxation mechanism, electronic interaction anisotropy, in collisions between these ``submerged-shell,'' $L\ensuremath{\ne}0$ atoms. These large Spin Relaxation rates imply that evaporative cooling of these atoms in a magnetic trap will be highly inefficient.
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large Spin Relaxation rates in trapped submerged shell atoms
APS, 2010Co-Authors: Colin B Connolly, Charles S Doret, Wolfgang Ketterle, John M DoyleAbstract:Spin Relaxation due to atom–atom collisions is measured for magnetically trapped erbium and thulium atoms at a temperature near 500 mK. The rate constants for Er–Er and Tm–Tm collisions are 3.0 × 10 10 cm 3 s 1 and 1.1 × 10 10 cm 3 s 1 , respectively, 2–3 orders of magnitude larger than those observed for highly magnetic S-state atoms. This is strong evidence for an additional, dominant, Spin Relaxation mechanism, electrostatic anisotropy, in collisions between these “submerged-shell” L 6 0 atoms. These large Spin Relaxation rates imply that evaporative cooling of these atoms in a magnetic trap will be highly inefficient.
Alois Arrighi - One of the best experts on this subject based on the ideXlab platform.
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strongly anisotropic Spin Relaxation in graphene transition metal dichalcogenide heterostructures at room temperature
Nature Physics, 2018Co-Authors: Antonio L Benitez, J F Sierra, Williams Savero Torres, Alois Arrighi, F Bonell, Marius V Costache, Sergio O ValenzuelaAbstract:A large enhancement in the Spin–orbit coupling of graphene has been predicted when interfacing it with semiconducting transition metal dichalcogenides. Signatures of such an enhancement have been reported, but the nature of the Spin Relaxation in these systems remains unknown. Here, we unambiguously demonstrate anisotropic Spin dynamics in bilayer heterostructures comprising graphene and tungsten or molybdenum disulphide (WS2, MoS2). We observe that the Spin lifetime varies over one order of magnitude depending on the Spin orientation, being largest when the Spins point out of the graphene plane. This indicates that the strong Spin–valley coupling in the transition metal dichalcogenide is imprinted in the bilayer and felt by the propagating Spins. These findings provide a rich platform to explore coupled Spin–valley phenomena and offer novel Spin manipulation strategies based on Spin Relaxation anisotropy in two-dimensional materials. Large Spin–orbit coupling can be induced when graphene interfaces with semiconducting transition metal dichalcogenides, leading to strongly anisotropic Spin dynamics. As a result, orientation-dependent Spin Relaxation is observed.
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strongly anisotropic Spin Relaxation in graphene transition metal dichalcogenide heterostructures at room temperature
arXiv: Mesoscale and Nanoscale Physics, 2017Co-Authors: Luis A Benitez, J F Sierra, Williams Savero Torres, Alois Arrighi, F Bonell, Marius V Costache, Sergio O ValenzuelaAbstract:Graphene has emerged as the foremost material for future two-dimensional Spintronics due to its tuneable electronic properties. In graphene, Spin information can be transported over long distances and, in principle, be manipulated by using magnetic correlations or large Spin-orbit coupling (SOC) induced by proximity effects. In particular, a dramatic SOC enhancement has been predicted when interfacing graphene with a semiconducting transition metal dechalcogenide, such as tungsten disulphide (WS$_2$). Signatures of such an enhancement have recently been reported but the nature of the Spin Relaxation in these systems remains unknown. Here, we unambiguously demonstrate anisotropic Spin dynamics in bilayer heterostructures comprising graphene and WS$_2$. By using out-of-plane Spin precession, we show that the Spin lifetime is largest when the Spins point out of the graphene plane. Moreover, we observe that the Spin lifetime varies over one order of magnitude depending on the Spin orientation, indicating that the strong Spin-valley coupling in WS$_2$ is imprinted in the bilayer and felt by the propagating Spins. These findings provide a rich platform to explore coupled Spin-valley phenomena and offer novel Spin manipulation strategies based on Spin Relaxation anisotropy in two-dimensional materials.
