NIST Sensor Improvement Brings Analysis Method into Mainstream Video Transcript (back to video)
At the National Institute of Standards and Technology just outside Washington, DC, there exists a mysterious, vault- like structure with thick cinder block walls ...
A single narrow slit for a window … and a massive door keeping the curious at bay.
Believe it or not … all of this protection is needed so that a small block of silicon can become an important tool in the development of advanced materials for tomorrow’s technologies.
But the vault’s days on the job may soon be numbered … that is, if researchers at NIST’s center for neutron research and the University of Waterloo’s institute for quantum computing in Canada have their way.
The silicon block currently housed within the NIST vault is the heart and soul of an instrument known as an interferometer.
It’s a device that allows researchers to use neutrons to study the nuclear and magnetic structure of materials just like doctors use x-rays to examine the internal structures of the body.
Michael Huber (on camera): We can look at magnetic materials for use in electronics, hard drives, and better more efficient electronic devices.
Neutrons … which have no charge … cannot be focused by glass lenses to form images the way that light beams can.
Instead … scientists use a silicon block with three, precisely machined thin blades that act like mirrors to direct the neutron beam onto its target.
Unfortunately … these blades are extremely sensitive to temperature changes and vibrations.
That’s why NIST has been conducting its neutron exams inside the protective vault … a structure that features special shock absorbers and temperatures kept constant to a few thousandths of a degree Celsius.
Michael Huber (on camera):
And the problem is we have to maintain the initial conditions of the interferometer for weeks or even months or even years at a time.
Also complicating the process was the fact that all of the shielding from environmental hazards kept the interferometer much too distant from the source of the neutrons.
Dmitry Pushin (on camera):
So only few neutrons come to this specific location because most of them just go all over the place. … that’s why there’s only few neutrons come to the device so we have to do our measurements for a long time.
The NIST-Waterloo team … however … found a novel way to sidestep the problems with the current system.
They discovered that the stability of the silicon block could be dramatically increased by simply adding a fourth blade at an optimal location.
Michael Huber (on camera) With the new 4-blade interferometer, we’re able to move within about a half of a meter to that same source, and so that increases your intensity by more than a factor of 10.
The amount of improvement is so impressive that the new interferometer will generate data that is far more accurate than before in a fraction of the time.
And best of all … it can be housed inside a box the size of a small refrigerator instead of the massive and complex vault.
Dmitry Pushin (on camera):
We have some experiments which run for several months and we can shorten each of these experiments to just a few weeks. So usually when we run one or two experiments a year, we can now run ten experiments a year. So we can perform better, we can study stuff which we never studied before because we really didn’t have time to do it.
And that’s good news because the neutron interferometer is one of best tools for studying thin films and materials made of many thin layers … items that will be critical for the next generation of electronics … medicines … automobiles … and many other technologies.