Model for petahertz optical memory based on a manipulation of the optical-field-induced current in dielectrics

A new physical insight into the ultrafast information communication can be gained from the reversible and robust petahertz (PHz, 10¹⁵ Hz) current induced by a strong few-cycle optical waveform in large band-gap dielectrics. We explore an asymmetric conduction of the petahertz current using a heterojunction of low-hole-mass and low-electron-mass dielectrics and devise various functionalities enabling the petahertz signal processing, like diode, switch, and diode transistor. We then propose a model of one-bit optical nonvolatile random-access memory (RAM) by assembling those functionalities and demonstrate its petahertz operation. Further, we suggest the scalability up to a four-bit data manipulation based on the 2 ×2 array of four one-bit RAM elements.