05/09/2024
https://sciencesprings.wordpress.com/2024/09/04/from-the-research-lab-of-electronics-in-the-department-of-electrical-engineering-and-computer-science-in-the-school-of-engineering-at-the-massachusetts-institute-of-technology-nanostr/
From The Research Lab of Electronics In The Department of Electrical Engineering and Computer Science In The School of Engineering At The Massachusetts Institute of Technology: “Nanostructures enable on-chip lightwave-electronic frequency mixer”
http://www.rle.mit.edu/about/
https://www.eecs.mit.edu/
https://engineering.mit.edu/
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Imagine how a phone call works: Your voice is converted into electronic signals, shifted up to higher frequencies, transmitted over long distances, and then shifted back down so it can be heard clearly on the other end. The process enabling this shifting of signal frequencies is called frequency mixing, and it is essential for communication technologies like radio and Wi-Fi. Frequency mixers are vital components in many electronic devices and typically operate using frequencies that oscillate billions (GHz, gigahertz) to trillions (THz, terahertz) of times per second.
Now imagine a frequency mixer that works at a quadrillion (PHz, petahertz) times per second — up to a million times faster. This frequency range corresponds to the oscillations of the electric and magnetic fields that make up light waves. Petahertz-frequency mixers would allow us to shift signals up to optical frequencies and then back down to more conventional electronic frequencies, enabling the transmission and processing of vastly larger amounts of information at many times higher speeds. This leap in speed isn’t just about doing things faster; it’s about enabling entirely new capabilities.
Lightwave electronics (or petahertz electronics) is an emerging field that aims to integrate optical and electronic systems at incredibly high speeds, leveraging the ultrafast oscillations of light fields. The key idea is to harness the electric field of light waves, which oscillate on sub-femtosecond (10^-15 seconds) timescales, to directly drive electronic processes. This allows for the processing and manipulation of information at speeds far beyond what is possible with current electronic technologies. In combination with other petahertz electronic circuitry, a petahertz electronic mixer would allow us to process and analyze vast amounts of information in real time and transfer larger amounts of data over the air at unprecedented speeds. The MIT team’s demonstration of a lightwave-electronic mixer at petahertz-scale frequencies is a first step toward making communication technology faster, and progresses research toward developing new, miniaturized lightwave electronic circuitry capable of handling optical signals directly at the nanoscale.
In the 1970s, scientists began exploring ways to extend electronic frequency mixing into the terahertz range using diodes. While these early efforts showed promise, progress stalled for decades. Recently, however, advances in nanotechnology have reignited this area of research. Researchers discovered that tiny structures like nanometer-length-scale needle tips and plasmonic antennas could function similarly to those early diodes but at much higher frequencies.
A recent open-access study published in "Science Advances" by Matthew Yeung, Lu-Ting Chou, Marco Turchetti, Felix Ritzkowsky, Karl K. Berggren, and Phillip D. Keathley at MIT has demonstrated a significant step forward.
https://www.science.org/doi/10.1126/sciadv.adq0642
See the science paper for instructive material with images.
See the full blog post.
The demonstration of a lightwave-electronic mixer at petahertz-scale frquencies is a first step toward making communication technology faster and progresses research toward developing new, miniaturized lightwave electronic circuitry capable of handling optical signals directly at the nanoscale. Image: Sampson Wilcox/Research Laboratory of Electronics
