The effect of surface bond reconstruction of thermal contact surfaces on phonon transport in atomic wire

Abstract

The effect of surface bond reconstruction ͑SBR͒ of Si contact surfaces on phonon transport in Si atomic wire is investigated. Green's function method is applied to calculate the thermal conductance and local heat currents. Results show that the phonon transport in atomic wires is enhanced significantly by SBR at the thermal contact surface. A blue shift for phonon transmission function is induced by the SBR.

Phonon transport in atomic chains coupled by thermal contacts: The role of buffer layer

“…The effect of SBR is analyzed in details in our previous paper. 9,10 One more important factor that affects phonon transport is the nonlinear interaction between atoms in atomic wire. Although there are lots of studies on phonon transport, most of them are considered ballistic phonon transport that leads to serious inaccuracy in phonon transport properties characterization and thermal conductance calculation.…”

Influence of electron scatterings on thermoelectric effect

“…Therefore, the strategies of developing high ZT device are improving the electronic TE efficiency and reducing the lattice thermal conductivity [14]. Currently, most of the efforts are put in to reduce the lattice thermal conductivity by investigation the phonon transport, which can be found in our previous works [11][12][13]. However, more attentions needs to be paid on the electron transport, as the electronic TE efficiency limits the performance of TE device significantly [14].…”

Investigation on transport properties in nanowires with contacts

“…However, this effect is ignored in most of the previous works, which motivates our interest in studying it. In chapter 3, the effect of SBR and anharmonicity are discussed [19,20,21].…”

“…In this chapter [20,21], the phonon transport properties in a silicon atomic wire coupled to two semi-infinite contacts, is investigated. Moreover, two effects on phonon transport are considered: one is the surface bond reconstruction (SBR) in thermal contacts, the other is the anharmonic effect in atomic wire.…”

“…The contact surface is set to be the (0,0,1) plane of silicon crystal. To take into account the non-equilibrium temperature in the thermal contact near the contact point between the contacts and the wire, we take out certain parts, denoted by LD and RD[20], in the left and right contact, and treated them as parts of the SiNW, as indicated byFig.15a. Furthermore, we defined LD (RD) as a collection of atoms in the left (right) contact, which are coupled to the atoms in the wire.…”