Over 150 years ago, James Clerk Maxwell proposed an idea that even some of the era’s leading scientists struggled to accept. A changing electric field, he argued, could produce effects similar to electrical current, even when no charged particles were physically moving. Known as displacement current, the concept would become one of the foundations of modern electromagnetism, helping explain how electromagnetic waves, including radio waves and visible light, propagate through space.
Semiconductor innovation has largely been driven by a different mechanism: moving electrons. From the transistor to the smartphone processor to the AI accelerator, progress has come from controlling the flow of charge through ever-smaller devices. But RF engineers have run into a different problem. As RF switches shrink, unwanted effects such as parasitic capacitance and contact resistance begin to dominate, and at advanced process nodes those parasitics can overwhelm the benefits of scaling.
That realization led Dr. Mohammad Samizadeh Nikoo and Hua Wang, professor of electrical engineering at ETH Zurich, to ask a question: what if the next breakthrough in RF switching did not come from optimizing another transistor? Instead of relying on conventional transistor operation, they designed a switch that uses displacement fields and quantum tunneling currents, drawing on a mechanism rooted in Maxwell’s original framework.
The research was conducted while Nikoo was a postdoctoral researcher in Wang’s IDEAS Group at ETH Zurich. Nikoo is now an assistant professor at Nanyang Technological University in Singapore. Their findings were published in January 2026 in Nature Electronics in a paper titled “High-power millimetre-wave switches on silicon using displacement fields and tunnelling currents.”
Cross-sectional EDX image of fabricated DFT switches using a 45 RF-SOI process.
Turning the idea into a working device took more than a promising theory. Wang’s group has built an extensive partnership with GlobalFoundries through GF’s University Partnership Program, which gives university researchers access to advanced GF technologies along with design and technical support. The team built the switch on GF’s commercial 45nm RF-SOI platform using a “zero-change” approach — no custom fabrication, no specialized manufacturing flow, just elements of an existing commercial process assembled to operate through a different physical mechanism. Wang notes that the clean substrates and low parasitics of GF’s CMOS SOI technology were key to the device’s success.
The results were striking: sub-30-picosecond switching, more than 10 times higher power handling than conventional transistor-based switches on the same platform and significant gains in linearity and parasitics.
We spoke with Nikoo and Wang about why RF hit a wall, what changes when you switch with fields instead of electrons and where a device like this could end up. The conversation has been edited for length and clarity.