Proposal for an input interface and multi-output structures of all-spin logic circuits based on magnetic tunnel junction

摘要

This study proposes an input interface based on a magnetic tunnel junction (MTJ) to initialise the magnetisation directions of all-spin logic (ASL) circuits. It is convenient to input logic 0 and logic 1 to ASL circuits by changing the current direction into the MTJ. The impacts of current density, tunnel magneto-resistance (TMR), and resistance-area product (RA) on the input interface are studied. The results indicate that smaller TMR and RA of the materials are helpful in reducing the energy dissipation of the input interface without increasing the delay time, and the current density has a large range of options. Moreover, two kinds of output structures, single-input multi fan-out (SIMF) and multi-input single fan-out (MISF), are proposed to provide signals for subsequent ASL circuits. It is found that the SIMF structure is suitable for the condition of fewer output terminals, but the MISF structure is especially useful for large-scale ASL circuits that contain many identical input ports. The above-mentioned conclusions can provide guidelines for optimising the device materials and output structures of ASL circuits.