Tiny ring laser accurately detects and counts nanoparticles

Counting Nanoparticles with Lasers J. ZHU, L. HE, S. K. OZDEMIR, AND L. YANG/WUSTL Researchers at Washington University in St. Louis have turned an acoustic phenomenon familiar to those who have visited the Statuary Hall in the U.S. Capitol Building or St. Paul's Cathedral in London into a high-resolution nanoparticle detector. Using a ring-shaped micro-laser, the sensor can detect and count individual viruses or synthetic and biological nanoparticles with single particle resolution. The sensor is what's known as a "whispering gallery resonator" and relies on the same principles as those acoustic spaces (like the aforementioned Capitol and cathedral galleries) where whispers on one side of the room can be heard directly on the other side thanks to the unique properties of the shape of the space. But unlike the acoustic spaces (which are usually in round, domed spaces) that have audible sweet spots, the new sensor has optical sweet spots. There's a lot of optical science that goes into this, and we're not goin

"The light used for sensing is generated inside the resonator itself, and so it is purer than the light in the passive sensor," says Yang "When the light is not that pure, you might not be able to see small frequency changes.
"Now you just need a light source to excite the optical medium," says Yang, "and you can use a cheap laser diode for that instead of an expensive tunable laser.
"When the line broadening is comparable to the change in splitting, then you're done," says Yang. "However, the whole resonator is fabricated on the chip, so you could just move on to the next resonator if necessary."
"By controlling the overlap of the pump light with the gain medium, you can excite more than one laser line," says Sahin Kaya Ozdemir, PhD, a research associate and co-author.

Tiny ring laser accurately detects and counts nanoparticles

(PhysOrg.com) -- A microlaser no bigger than a pinprick can accurately detect and count individual viruses, the particles that jumpstart cloud formation or those that contaminate the air we ...

Tue 28 Jun 11 from Phys.org

Tiny ring laser accurately detects and counts nanoparticles, Tue 28 Jun 11 from Labspaces.net

Tiny ring laser accurately detects and counts nanoparticles, Tue 28 Jun 11 from R&D Mag

Tiny ring laser accurately detects and counts nanoparticles, Tue 28 Jun 11 from Eurekalert

Ring of Laser Light Can Count Individual Viruses and Nanoparticles

Counting Nanoparticles with Lasers J. ZHU, L. HE, S. K. OZDEMIR, AND L. YANG/WUSTL Researchers at Washington University in St. Louis have turned an acoustic phenomenon familiar to those who ...

Wed 29 Jun 11 from Popular Science

Tiny Ring Laser Detects and Counts Nanoparticles

A microlaser can accurately detect and count individual viruses and other tiny particles.

Wed 29 Jun 11 from U.S. News

Tiny Ring Laser Accurately Detects, Counts Nanoparticles

A microlaser no bigger than a pinprick can accurately detect and count individual viruses, the particles that jumpstart cloud formation or those that contaminate the air we breathe.By Diana ...

Wed 29 Jun 11 from RedOrbit

Scientists Develop Microlasers to Count Nano-Scale Synthetic or Biological Particles

By Cameron Chai A microlaser in the size of a pinprick has been developed that can identify and count individual viruses accurately. It can also be used to count the nanoparticles that initiate ...

Wed 29 Jun 11 from AZoNano

  • Pages: 1

Total number of sources: 8

Bookmark

Bookmark and Share