A Bizarre Adventure That Begins in Jujutsu Kaisen

Chapter 126 A Researcher's Day - Part 1

Ashunad recently became an "ordinary researcher".

His work involves studying two-dimensional materials with a thickness of only one to a few atomic layers.

The research institute he works for belongs to the Helios Agency, a magical organization named after the ancient Greek sun god.

Some of the institute's research projects are directly related to the development of the EU's most cutting-edge energy project, the tokamak magnetic confinement fusion device.

These types of devices have extremely stringent requirements for the materials' high temperature resistance, radiation resistance, and high thermal conductivity.

Therefore, the institute recruited a large number of people like him to exhaustively search for all possible combinations on the periodic table, hoping to find suitable candidate materials in the vast microscopic world.

At 10:30 a.m., a time that is quite leisurely for people in some countries who start at 8 a.m., Ashunad swiped his card to pass through the heavy alloy gate of the research institute and changed into a white lab coat near the coat rack at the entrance.

The first thing he does every morning is to check the laboratory thermometer and barometer to confirm that the environmental parameters are within the allowable fluctuation range. Then he opens the recording software on the computer, creates a new page of the experimental log, and fills in the real-time data.

Next, he continued to check the temperature of the sample inside the scanning tunneling microscope (STM).

If the temperature rises significantly by 1K or more, he will immediately check the liquid level in the huge Dewar flask that supplies liquid helium.

If there is still liquid helium remaining and the temperature increase is not significant, then there is usually no major problem.

If the remaining liquid helium is sufficient but the temperature rise is significant and continuous, further investigation is needed.

The most common problem is that the sample chamber door of the STM is not closed tightly, causing heat leakage. Simply opening and closing it again will solve the problem.

Another possibility is that the heat exchange contact screws connecting the sample stage and the cold head loosened due to thermal expansion and contraction after multiple cycles.

This requires tightening it about a quarter turn with an Allen wrench to ensure a tight contact.

After this step is completed, the temperature curve on the monitoring screen will often start to turn downward within a few minutes.

I'm lucky today; the temperature curve is as stable as a salted fish, everything is normal.

Ashunad breathed a sigh of relief and began his official work.

I'm ready! Bring it on, you wretched materials!

He first used a slender gripping tool called a "shake bar" to pick up a processed metal single crystal sample from the vacuum storage rack and transfer it to a special fixture at the end of the robotic arm.

Next, he manipulated the robotic arm to move along the preset track to the argon ion etching equipment, closed the hatch, shut down the ion pump that maintained the high vacuum, opened the argon gas valve, and applied a high-voltage electric field of several thousand volts.

In an ultra-high vacuum environment, argon gas is ionized into argon ions, which are continuously bombarded on the sample surface under the acceleration of an electric field, stripping away any impurities that may be present.

After the bombardment ended, Ashunad restarted the ion pump and turned on the heating power.

The miniature heating wire integrated inside the robotic arm begins to heat and anneal the metal single crystal.

After three rounds of argon etching and annealing, he used a robotic arm to transfer the processed sample to the molecular beam epitaxy equipment, where an ultrathin film with a thickness of only one atom was deposited.

Finally, the sample carrying the target molecule is placed into the sample chamber, ready to receive the scanning tip that can "see" atoms and explore electronic states.

However, after the scan began, the low-frequency signal representing tunnel current noise on the screen had an abnormally large amplitude, and the topographic image was covered with interference stripes like television snow.

This is a persistent problem caused by the aging of system hardware.

Ashundard began experimenting with several methods for "humanity's first taming of a needle tip":

Adjust the height of the probe tip by pushing or pulling it to change the distance between it and the sample surface.

Apply short, high-voltage pulses to push away any impurities that may have been adsorbed by the needle tip:

By very lightly "poking" an unimportant area on the sample surface with the tip of a needle, the atomic configuration at the tip of the needle is changed;

Adjust the feedback parameters of the tunneling current to make the needle tip "wobble" slightly in place.

But after he tried everything, the annoying noise stubbornly lingered in the signal, showing no signs of improvement, so he had to resample.

This is a last resort, which is both time-consuming and risky, but sometimes it can miraculously solve some problems caused by minute contact defects, thermal stress deformation, or nanometer-level displacement of the sample position.

After resampling, the noise intensity did decrease somewhat, and the image was barely recognizable, but it was far from achieving the ideal research-grade quality.

Moreover, Ashundard also discovered that the steps on the surface of the metal single crystal, which should have been wide and flat, became very "fragmented".

The deposited molecules are randomly distributed along the edges of these broken steps, making them appear very thick.

Tomorrow I need to reprocess the single-crystal surface and then try a lower deposition rate and substrate temperature.

Ashunad silently made a mental note of the idea and briefly recorded the problems he encountered that day in the corresponding section of his electronic log.

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