New Transmission Electron Microscope Developed by University of Arizona Researchers
TapTechNews August 22nd news, researchers at the University of Arizona in the US have developed a new type of transmission electron microscope, which is so fast that it can achieve the observation of moving electrons.
TapTechNews noted that this research result was published in the journal Science Advances on August 21st. Researchers hope to conduct in-depth research on microscopic particles through this new microscope to reveal the mystery of electron movement.
Electrons move at a speed of approximately 1,367 miles per second and can circle the earth in 18.4 seconds. Therefore, to capture the trajectory of electrons requires extremely high shooting speed. Researchers achieved this goal by generating electron pulses that last only one attosecond (10 to the minus 18th second).
The research team said that this new microscope is like a high-performance camera on a smartphone, which can help scientists observe phenomena that were previously impossible to see, such as the movement of electrons. Through this microscope, scientists are expected to better understand the quantum physical properties and movement laws of electrons.
The arrangement and rearrangement of electrons is a fundamental problem in the fields of physics and chemistry, but due to the extremely fast movement speed of electrons, it is very difficult to study them. In the early 21st century, physicists developed methods to generate attosecond-level pulses, providing new tools for studying the movement of electrons. This achievement won the 2023 Nobel Prize in Physics.
By shortening the exposure time of the microscope to the level of several attoseconds, physicists have studied the charge transfer of electrons, their behavior in semiconductors and liquid water, and the breaking process of chemical bonds between atoms. However, even the attosecond-level exposure time is still not fast enough to capture the movement of a single electron.
To solve this problem, the researchers improved the electron gun, enabling it to generate electron pulses that last only one attosecond. These pulses irradiate the sample being studied, and when the electrons pass through the sample, their speed slows down and changes the shape of the electron beam wavefront. The slowed-down electron beam is then magnified by a lens and irradiates a fluorescent material that glows when irradiated by the electron beam.
By combining the electron pulse with two precisely synchronized light pulses (used to excite the electrons in the material into a moving state and assist in the generation of the electron pulse respectively), the researchers can detect the ultrafast movement of electrons inside atoms.
The research team said that their transmission microscope has achieved attosecond time resolution and named it the atomic microscope, which is the first time that the movement trajectory of electrons can be observed.