Dual-band microwave detector based on magnetic tunnel junctions

The spin-torque diode effect has enabled a nanoscale category of microwave detectors, which are characterized by ultrahigh sensitivities and can work at sub-μW input power. Here, we develop such detectors having a dual-band rectification curve centered at the frequencies f1 and f2 and with a rectified voltage of opposite sign (V f 1 > 0 and V f 2 < 0). By selecting the proper bias current and field, the sensitivity is larger than 8000 mV/mW. The physics behind this behavior is the simultaneous excitation of different magnetization oscillation modes and the injection locking mechanism. This dual-band microwave detector could find potential applications in the Internet of Things by reducing the size and the power consumption for signal demodulation in a binary frequency shift keying modulation/demodulation scheme.