Plasmonic ferroelectric tunnel junction random access memory

We demonstrate a plasmonically driven bi-stable random-access memory based on a ferroelectric tunnel junction. Surface plasmons (SP) are excited on a metal-insulator-metal (MIM) structure consisting of a 5nm HfO2 layer sandwiched between Au electrodes using laser light having a central wavelength of 800nm. Electrons are excited in the metallic electrodes by the SP and tunnel through the HfO2 to the opposite electrode. The direction of the current depends on the state of ferroelectric polarization in the HfO2 layer and the population of the trap states at the metal-insulator interfaces. Each direction of tunnelling current flow corresponds to a different state of the device. Switching between the states is facilitated by application of a 0.5 V bias and exposure to 800 nm laser light. Notably, the device can be read for up to an hour after the bias voltage is removed, indicating short term non-volatility. These results open a new pathway for the integration of nanoplasmonic and nanoelectronic circuits for the next generation of optical computing.