The February 2023 issue of IEEE Spectrum is here!

Close bar

Nose Works Like a Scanning Tunneling Microscope

Researchers upend understanding of olfactory organs with quantum tunneling experiment

3 min read

Flash memory, scanning tunneling microscopes...and a fly’s sense of smell. According to new research, the same strange phenomenon—quantum tunneling—makes all three possible. If confirmed, the discovery could pave the way for a new generation of artificial scents, from perfumes to pheromones—and, perhaps someday, artificial noses.

The conventional theory of smell holds that the nose’s chemical receptors—some 400 different kinds in a human nose—sense the presence of odorant molecules by a lock-and-key process that reads the odorant’s physical shape. That theory has some problems, though. For instance, ethanol (which smells like vodka) and ethanethiol (which smells like rotten eggs) have essentially the same shape, differing from each other by only a single atom. (Ethanol is C2H6O, and ethanethiol is C2H6S.)

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
Illustration showing an astronaut performing mechanical repairs to a satellite uses two extra mechanical arms that project from a backpack.

Extra limbs, controlled by wearable electrode patches that read and interpret neural signals from the user, could have innumerable uses, such as assisting on spacewalk missions to repair satellites.

Chris Philpot

What could you do with an extra limb? Consider a surgeon performing a delicate operation, one that needs her expertise and steady hands—all three of them. As her two biological hands manipulate surgical instruments, a third robotic limb that’s attached to her torso plays a supporting role. Or picture a construction worker who is thankful for his extra robotic hand as it braces the heavy beam he’s fastening into place with his other two hands. Imagine wearing an exoskeleton that would let you handle multiple objects simultaneously, like Spiderman’s Dr. Octopus. Or contemplate the out-there music a composer could write for a pianist who has 12 fingers to spread across the keyboard.

Such scenarios may seem like science fiction, but recent progress in robotics and neuroscience makes extra robotic limbs conceivable with today’s technology. Our research groups at Imperial College London and the University of Freiburg, in Germany, together with partners in the European project NIMA, are now working to figure out whether such augmentation can be realized in practice to extend human abilities. The main questions we’re tackling involve both neuroscience and neurotechnology: Is the human brain capable of controlling additional body parts as effectively as it controls biological parts? And if so, what neural signals can be used for this control?

Keep Reading ↓Show less
{"imageShortcodeIds":[]}