Proposal for a dual-gate spin field effect transistor: A device with very small switching voltage and a large ON to OFF conductance ratio

We propose a new dual gate spin field effect transistor (SpinFET) consisting of a quasi one-dimensional semiconductor channel sandwiched between two half-metallic contacts. The gate voltage aligns and de-aligns the incident electron energy with Ramsauer resonance levels in the channel, thereby modulating the source-to-drain conductance. The device can be switched from ON to OFF with a few mV change in the gate voltage, resulting in exceedingly low dynamic power dissipation during switching. The conductance ON/OFF ratio stays fairly large (∼60) up to a temperature of 10 K. This conductance ratio is comparable to that achievable with carbon nanotube transistors.