Hydrogen-based quantum microscope visualizes minute changes in atoms

Physicists at the University of California, Irvine placed two bonded hydrogen atoms between a silver

scanning tunneling microscope (STM) probeand the test sample, consisting of a flat copper surface with small islands of copper nitride. With laser pulses lasting trillionths of a second at cryogenic temperatures in the ultra-high vacuum of the device, scientists were able to excite a hydrogen molecule and record changes in its quantum states. This allowed the STM to form "still" images of the sample at the atomic scale.

The researchers note that the hydrogen moleculeis an example of a two-tier system. Its orientation shifts between two positions: up and down and slightly tilted horizontally. Using a laser pulse, scientists force the system to cycle from the ground state to the excited state, which leads to a superposition of the two states. The duration of cyclic oscillations is vanishingly small - only a few tens of picoseconds. By measuring this "decoherence time" and cyclic periods, the scientists were able to see how the hydrogen molecule interacts with its environment.

Source: University of California, Irvine

Space between STM probe and sampleis only 0.6 nm. The microscope, assembled by the authors of the work, detects the smallest electric currents flowing in this space, receives spectroscopic readings confirming the presence of a hydrogen molecule and sample elements.

“The hydrogen molecule has become part of the quantummicroscope in the sense that wherever the microscope scanned, hydrogen was between the needle and the sample, says Wilson Ho, head of the study. “This is an extremely sensitive probe, allowing us to see deviations down to 0.1 angstroms. With this resolution, we saw how the charge distribution on the sample changes.”

High detail based on quantumThe coherence of hydrogen, according to physicists, can be very useful in scientific research and in the development of catalysts, the functioning of which often depends on surface defects on the scale of individual atoms.

Read more:

It has been hunted for centuries: what do we know about the planet Vulcan next to the Sun

Astronomers have found a planet near the Earth: it has a very strange orbit

Physicists figured out how to design and print the most delicious chocolate in the world