Superconductor ICs: the 100-GHz second generation

In the shadow of high-temperature superconductivity, 35 years of research in low-temperature superconductor ICs quietly comes to fruition, yielding the world's fastest circuits

16 min read
Superconductor ICs: the 100-GHz second generation


[1] Researchers have demonstrated simple digital frequency dividers with Josephson junctions that have 0.25-µm minimum features and that operate at data rates up to 770 Gb/s. They rely on rapid single flux quantum (RSFQ) circuits, whose speed grows as junction sizes shrink. At 0.25 µm, the junctions are intrinsically nonhysteretic, a good sign for the future of complex chips operating at clock frequencies of 100 GHz.

The fastest integrated circuits in the world today are unique for their technology as well as for their speed. They are made with a superconducting metal, niobium, rather than a compound semiconductor. Their exotic technology is based on Josephson junction devices and the transmission of single quanta of magnetic flux along superconductor interconnects.

Keep reading...Show less

This article is for IEEE members only. Join IEEE to access our full archive.

Join the world’s largest professional organization devoted to engineering and applied sciences and get access to all of Spectrum’s articles, podcasts, and special reports. Learn more →

If you're already an IEEE member, please sign in to continue reading.

Membership includes:

  • Get unlimited access to IEEE Spectrum content
  • Follow your favorite topics to create a personalized feed of IEEE Spectrum content
  • Save Spectrum articles to read later
  • Network with other technology professionals
  • Establish a professional profile
  • Create a group to share and collaborate on projects
  • Discover IEEE events and activities
  • Join and participate in discussions

"SuperGPS" Accurate to 10 Centimeters or Better

New optical-wireless hybrid makes use of existing telecommunications infrastructure

3 min read
illustration of man looking at giant smart phone with map and red "you are here" symbol

Modern life now often depends on GPS(short for Global Positioning System), but it can err on the order of meters in cities. Now a new study from a team of Dutch researchers reveals a terrestrial positioning system based on existing telecommunications networks can deliver geolocation info accurate to within 10 centimeters in metropolitan areas.

The scientists detailed their findings 16 November in the journal Nature.

Keep Reading ↓Show less
Close-up of a colorful semiconductor wafer held the white gloved hands of a clean room technician.

A 300-millimeter wafer from a GlobalFoundries fab in Dresden is full of advanced transistors. The industry will need to continue to produce more and better devices, argues the author.

Liesa Johannssen-Koppitz/Bloomberg/Getty Images

This is a guest post in recognition of the 75th anniversary of the invention of the transistor. It is adapted from an essay in the July 2022 IEEE Electron Device Society Newsletter. The views expressed here are solely those of the author and do not represent positions of IEEE Spectrum or the IEEE.

On the 75th anniversary of the invention of the transistor, a device to which I have devoted my entire career, I’d like to answer two questions: Does the world need better transistors? And if so, what will they be like?

Keep Reading ↓Show less

Fourth Generation Digitizers With Easy-to-Use API

Learn about the latest generation high-performance data acquisition boards from Teledyne

1 min read

In this webinar, we explain the design principles and operation of our fourth-generation digitizers with a focus on the application programming interface (API).

Register now for this free webinar!

Keep Reading ↓Show less