Researchers from UC San Diego are using vacuum tube technology to develop more efficient computer processors. The research could result in faster microelectronic devices and better solar panels. Their results are published in a paper in the journal Nature Communications.
Commonly thought of as a primitive precursor to the modern transistor, vacuum tubes were the building blocks of computers in the early 20th century, and computers built using them filled entire rooms or buildings.
The invention of the transistor in the mid-20th century allowed computers to be built much smaller, and paved the way for the computing revolution of the late 20th century. That being the case, the transistor is arguably the greatest invention in history.
However, transistors are far from perfect. The materials they’re made out of, semiconductors, have several disadvantages. They can only be made so small due to the laws of physics, and there’s an upper limit on how efficient they can be. We’re starting to hit those limits, so many researchers are looking for alternatives. And one group is taking looking back toward vacuum tubes for inspiration.
When current is run through a semiconductor, it has to pass through solid material, which slows it down the current and limits efficiency. Vacuum tubes don’t have that problem because the current travels through air. Creating miniature vacuum tubes could increase the efficiency of our electronics.
However, an essential component to a vacuum tube is free electrons in the air, which is difficult to create at the nanoscale. Typically, large voltages or powerful lasers are needed.
The researchers at UC San Diego have managed to overcome this hurdle by using special gold nanostructures combined with a low voltage and a low-power laser. The result is a tenfold increase in efficiency, and transistors that can operate with more power and less resistance than those that use semiconductors.
The next step for the group is to scale down the vacuum tubes and explore their many applications. If their research pans out, the computers of the future may be using technology from a century ago-just much smaller.