In magnetic logic, four basic Boolean logic operations can be programmed by a magnetic bit at room temperature with a high output ratio (>10 %). In the same clock cycle, benefiting from the built-in spin Hall effect, logic results can be directly written into magnetic bits using an all-electric method.

Complementary metal-oxide-semiconductor logic circuits used in conventional computers require frequent communication with external nonvolatile memory, causing the memory wall problem. Recently reported magnetic logic with reconfigurable logic operation and built-in nonvolatile memory can potentially bridge this gap. However, its high-frequency performance is not well studied. Here, we first perform experimental and theoretical investigation on the switching time of magnetic logic-memory devices combining magnetic units and negative differential resistance (NDR) of semiconductors. It is found that the switching time of S-type NDR (transistor circuits) in logic operations is ∼300 ns and determined by the transistor's internal turn-on properties. We then propose a magnetic logic-memory device by coupling the anomalous Hall effect in magnetic materials and the insulator-to-metal transition in VO2. Our device realizes reliable output (output ratio > 1000%), a low work magnetic field (<20 mT), and excellent high-frequency performance (switching time = 1–10 ns).

A magnetic-field-controlled non-volatile memory device is fabricated by coupling Hall effect and resistive switching effect. The non-volatile property of the device is due to the fact that the Hall voltage of the semiconductor changes the resistance state of the resistive switching unit. By changing the device configuration, the storage can be controlled by magnetic fields in different directions. The parameters of the semiconductors and the resistive switching units are experimentally investigated and simulated to optimize the performance of the devices. The key to increasing the ON/OFF ratio and reducing power consumption is finding a suitable resistance match between the semiconductor and the resistive switching unit. By enhancing the mobility of the semiconductor, the performance of the device can also be significantly improved. This hybrid device provides new insights into the manufacture of magnetic field controlled non-volatile memory devices with potential of integrating computing and storage functions.

Both semiconductor and magnetic material properties are highly dependent on the environment temperature, and this is one of the critical obstacles limiting the application of these materials at high temperatures. In this work, a negative differential resistance-assisted anomalous Hall effect-based magnetic device has been fabricated and its thermal stability has been studied. The magnetic device was found quite stable and gave a reliable output current ratio of >104% in the temperature range of 0 °C–100 °C. The load-line analysis was performed to study the mechanism of thermal stability of this device in 0 °C–100 °C. It was found that the magnetic device exhibits improved thermal stability, with resistance variation in the range of 0 °C–100 °C being reduced by ∼40% compared to semiconductor-only devices. This study suggests that integrating magnetic and semiconductor properties together not only offer flexibility to integrate a number of applications in one simple device but also possible to provide thermal stability.

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