The new device is capable of measuring fast movements at the nanoscale

A new nanoscale device has just been developed at the JILA Institute (the collaboration between the NIST Institute and the University of Colorado in Boulder) - a small yellow metal cluster that vibrates 40 million times a second, the number of times This vibration is measured by ' leaping ' electrons - which can speed up the tunnel effect electron microscope (STM) by 500 times, paving the way for scientists to observe vibrating atoms Dynamic with high definition according to real-time system.

This new device is capable of measuring the oscillation of a metal beam, or, more precisely, the space between it and a conductive point that is only about the size of a single atom, based on the speed of the electron '. The tunnel 'goes through that gap. This study is the first study to use ' atomic point contact ', a key component of the STM machine, to detect and store the vibrations of nanoscale mechanical devices at frequencies'. its resonance ', where the machine vibrates like a vibrating fork.

The new JILA machine has the ability to measure movements at the nanoscale.The slow motion simulator of the nanoscale motion detector of the JILA Institute shows the oscillation of soft metal beams, only 100 nanometers thick, when it is affected by an electric current at the dot (black). .Red indicates the biggest position change since the resting state.(Photo: K. Lehnert / JILA)

Although the JILA institute's new technique does not need to be as accurate as the more complex and cold methods used to measure the movements of very small devices, it integrates a number of innovative properties with together.

These properties include the ability to minimize unwanted random electronic ' noise ' as well as the ability to measure metal beam vibrations due to reverse effects or recoil (similar to the shock of a gun when shoot) cause. Sensitivity is possible because the atomic point contact acts as an amplifier of these otherwise imperceptible elements, and the yellow metal beam is small and light enough - only 100 nanometers thick, long. 5.6 microns and 220 nanometers wide - to respond to single electrons.

This new method involves bringing this sharp point into a nanometer-sized yellow metal beam. An electric current is created, running through the gap across the gap, until an increase in resistance indicates that the electrons are ' passing through the tunnel ' across the gap (a phenomenon observed only in the original size. death). The size of the gap is then observed based on vibrations in the current.

The wave motion of the metal beam is measured 10 to 100 times more accurately than the result of a typical STM machine. That's because vibrations are measured using microwave electronics, a way that is much faster than the audio frequency technique used specifically for STMs, so that the main level can be achieved. Higher body. Microwave measurement techniques can be applied to STM machines.

Thanh Van