Figure 1

(Color online) A schematic showing the top view of the proposed device. The channel is connected to ferromagnetic and/or half-metallic leads arranged in an antiparallel configuration. A spin array, which could, for example, be paramagnetic traps at the $\mathrm{Si}\text{−}\mathrm{Si}{\mathrm{O}}_2$ interface of an FET (Ref. 9) or ferromagnetic atoms trapped inside a host molecule attached to the channel (Ref. 17), is placed in close proximity to the channel and affects the conduction by spin flip scattering through exchange coupling with channel electrons.Reuse & Permissions

Figure 2

$I\text{−}V$ characteristics for different spin excitations according to Eqs. (1, 2, 3a, 3b) for ideal contact. The simulation is done using the following parameters: $D=m^{*}LW∕\left(2\pi {\hslash }^2\right)$, where $L=100\mathrm{nm}$ and $W=300\mathrm{nm}$, while $m^{*}=0.2m_0$, $m_0$ being the free electron mass. $N_I={\tilde{N}}_{I}LW$ where ${\tilde{N}}_I\approx {10}^{11}∕{\mathrm{cm}}^2$, $T=300\mathrm{K}$ and $J_0=0.02\mu \mathrm{eV}$, which corresponds to an exchange frequency (Ref. 1) of $30\mathrm{MHz}$.Reuse & Permissions

Figure 3

$I\text{−}V$ calculated for nonideal contact. The injection efficiencies of the source and drain were assumed to be 60% and 40%, respectively. Two spin excitations of $\hslash \omega =2.5$ and $5\mathrm{meV}$ were assumed. (a) Total current. No features can be detected due to large contribution from ballistic current. (b) The second derivative of the total current. The peaks retain the information of spin scattering. (c) Dotted line—antisymmetric part of the total current: $I_{\mathrm{asym}}=I\left(V\right)-I(-V)$; solid line—second derivative of the antisymmetric part. (d) Dotted line—symmetric part of the total current: $I_{\mathrm{sym}}=I\left(V\right)+I(-V)$; solid line—second derivative of the symmetric part. The contact couplings are roughly around $0.1\mathrm{eV}$. All other transport parameters are the same as were indicated in Fig. 2. The temperature was set to $T=3\mathrm{K}$. This is necessary to distinguish among the multiple peaks, which will be otherwise washed away because of temperature broadening.Reuse & Permissions