  We have designed a passive spintronic diode based on a single skyrmion
stabilized in a magnetic tunnel junction and studied its dynamics induced by
voltage-controlled anisotropy (VCMA) and Dzyaloshinskii-Moriya interaction
(VDMI). We have demonstrated that the sensitivity (rectified voltage over input
microwave power) with realistic physical parameters and geometry can be larger
than 10 kV/W which is one order of magnitude better than diodes employing a
uniform ferromagnetic state. Our numerical and analytical results on the VCMA
and VDMI-driven resonant excitation of skyrmions beyond the linear regime
reveal a frequency dependence on the amplitude and no efficient parametric
resonance. Skyrmions with a smaller radius produced higher sensitivities,
demonstrating the efficient scalability of skyrmion-based spintronic diodes.
These results pave the way for designing passive ultra-sensitive and energy
efficient skyrmion-based microwave detectors.
