Demonstration of resonant tunneling effects in metal-double-insulator-metal (MI(2)M) diodes

Although the effect of resonant tunneling in metal-double-insulator-metal (MI(2)M) diodes has been predicted for over two decades, no experimental demonstrations have been reported at the low voltages needed for energy harvesting rectenna applications. Using quantum-well engineering, we demonstrate the effects of resonant tunneling in a Ni/NiO/Al(2)O(3)/Cr/Au MI(2)M structures and achieve the usually mutually exclusive desired characteristics of low resistance ([Formula: see text] 13 kΩ for 0.035 μm(2)) and high responsivity (β(0) = 0.5 A W(−1)) simultaneously. By varying the thickness of insulators to modify the depth and width of the MI(2)M quantum well, we show that resonant quasi-bound states can be reached at near zero-bias, where diodes self-bias when driven by antennas illuminated at 30 THz. We present an improvement in energy conversion efficiency by more than a factor of 100 over the current state-of-the-art, offering the possibility of engineering efficient energy harvesting rectennas.