Mesoscopic phonon transmission through a nanowire-bulk contact

We have developed an efficient scalable kernel method for thermal transport in open systems, with which we have computed the thermal conductance of a junction between bulk silicon and silicon nanowires with diameter up to 10 nm. We have devised scaling laws for transmission and reflection spectra, which allow us to predict the thermal resistance of bulk-nanowire interfaces with larger cross sections than those achievable with atomistic simulations. Our results indicate the characteristic size beyond which atomistic systems can be treated accurately by mesoscopic theories.

Section: Resultssupporting

confidence: 67%

Atomistic calculation of the thermal conductance of large scale bulk-nanowire junctions

Duchemin

Donadio

2011

“…[6] The interplay between the RSOI and DSOI leads to a significant change in the transport property. There are a few works on the effects of the competition between these two types of SOI on the transport properties of 2DEG, [7,8,9]especially in mesoscopic rings [10]. The circular photogalvanic effect can be used to separate the contribution of the RSOI and DSOI, and the relative strengths of the RSOI and DSOI can be extracted from the photocurrent.…”

Section: Introductionmentioning

confidence: 99%

Anisotropic spin transport in two-terminal mesoscopic rings: Rashba and Dresselhaus spin-orbit interactions

Wang

Chang

2008

We investigate theoretically the spin transport in two-terminal mesoscopic rings in the presence of both the Rashba spin-orbit interaction (RSOI) and the Dresselhaus spin-orbit interaction (DSOI).We find that the interplay between the RSOI and DSOI breaks the original cylindric symmetry of mesoscopic ring and consequently leads to the anisotropic spin transport, i.e., the conductance is sensitive to the positions of the incoming and outgoing leads. The anisotropic spin transport can survive even in the presence of disorder caused by impurity elastic scattering in a realistic system.

“…We can choose a new basis vector such that the charge Hall conductance vanishes [34], however, the physics conclusion Eq. (30) [see also Eq.…”

Section: Berry Phase and Spin Currentmentioning

confidence: 99%

Spin-torque current induced by topological Berry phase in a two-dimensional system with generick-linear spin-orbit interaction

Chen

2014

The Berry phase on the Fermi surface and its influence on the conserved spin current in a twodimensional system with generic k-linear spin-orbit interaction are investigated. We calculate the response of the effective conserved spin current to the applied electric field, which is composed of conventional and spin torque currents, by using the Kubo formula. We find that the conventional spin current is not determined by the Berry phase effect. Remarkably, the spin torque Hall current is found to be proportional to the Berry phase, and the longitudinal spin torque current vanishes because of the Berry phase effect. When the k-linear spin-orbit interaction dominates the system, the Berry phase on the Fermi surface maintains two invariant properties. One is that the magnitude of the spin torque current protected by the Berry phase is unchanged by a small fluctuation of energy dispersion. The other one is that the change in the direction of the applied electric field does not change the magnitude of the spin torque current even if the energy dispersion is not spherically symmetric; i.e., the Berry phase effect has no dependence on the two-dimensional material orientation. The spin torque current is a universal value for all k-linear systems, such as Rashba, Dresselhaus, and Rashba-Dresselhaus systems. The topological number attributed to the Berry phase on the Fermi surface represents the phase of the orbital chirality of spin in the k-linear system. The change in the topological number results in a phase transition in which the orbital chirality of spin sz and −sz is exchanged. We found that the spin torque current can be experimentally measured.