On Chip Photothermoelectric Logic Gates with Sub-Picosecond Photothermal Response

Abstract

On-chip electronic devices driven by ultrafast light represent a promising approach to surpass traditional information processing speeds. However, practical implementation has been limited by the requirement for material with complex heterostructure and femtosecond lasers with high pulse energy, carrier-envelope phase stability, and few-cycle durations. To address this limitation, an on-chip logic gate is developed on a metallic material platform based on the photothermoelectric effect (PTE) and plasma resonance absorption of gold. By manipulating the light polarization, hot carrier migration is controlled, achieving a high polarization ratio and bipolar response. Meanwhile, time-resolved transient absorption spectroscopy demonstrates that the switching time is on the sub-picosecond scale. The logic gate used two picojoule-level laser pulses as inputs, outputting nanoampere-level currents with controllable polarity. This design provides a convenient fabrication process, promising for large-scale high speed logic computing devices.