Electronics at Optical Frequencies: From Key Principles to Applications*

Electronics has profoundly shaped modern society, ranging from telecommunications to precision measurements in scientific applications. Traditionally, electronics operates in the microwave to terahertz range, with transistors now approaching sub-picosecond switching times. Recent breakthroughs in ultrafast optics^1,2, however, have opened pathways towards operation at petahertz frequencies. Nevertheless, substantial challenges remain before electronics operating at optical frequencies can become a reality.

In this presentation, I will outline key principles essential for realizing optical frequency electronics, focusing particularly on electric-field rectification in gas- and solid-phase media. Additionally, I will discuss cutting-edge applications enabled by current technology, including phase detection³ and field-resolved spectroscopy^4,5. Finally, I will provide a perspective on future opportunities, ongoing challenges, and some open questions.

1. Krüger, M., Schenk, M. & Hommelhoff, P. Attosecond control of electrons emitted from a nanoscale metal tip. Nature 475, 78–81 (2011).

2. Ludwig, M. et al. Sub-femtosecond electron transport in a nanoscale gap. Nat. Phys. 16, 341–345 (2020).

3. Ritzkowsky, F. et al. On-chip petahertz electronics for single-shot phase detection. Nat Commun 15, 10179 (2024).

4. Bionta, M. R. et al. On-chip sampling of optical fields with attosecond resolution. Nat. Photonics 15, 456–460 (2021).

5. Yeung, M. et al. Lightwave-electronic harmonic frequency mixing. Science Advances 10, eadq0642 (2024).