Emitter-coupled spin-transistor logic

• First logic family with magnetoresistive semiconductor heterojunction transistors.
• Spintronic logic family with cascadable stages.
• High-permeability shielding material concentrates magnetic field.
• First logic family based on ECL to use the spin-degree of freedom.
• Potential to replace CMOS for general-purpose computing.

The recent invention of magnetoresistive bipolar spin-transistors makes possible the creation of new spintronic logic families. Here we propose the first logic family exploiting these devices, extending emitter-coupled logic (ECL) to achieve a greater range of basis logic functions. By placing the wire from the output stage of ECL logic elements near spin-transistors in other logic stages throughout the circuit, additional basis logic elements can be realized. These new logic elements support greater logic minimization, resulting in enhanced speed, area, and power characteristics. A novel magnetic shielding structure provides this logic family with the crucial ability to cascade logic stages. This logic family potentially achieves a power-delay product 10–25 times smaller than conventional ECL, and can therefore be exploited to increase the performance of very high-speed logic circuits while broadening the range of design choices for a variety of electronic applications.