After hearing Lin Xiao's words, Zhao Xian couldn't help but become confused.
Change the structure?
What structure should be replaced?
Lin Xiao continued to look at the data above, and did not directly answer his question, but said: "Yttrium barium copper oxide can directly reach the superconducting state by using cheap liquid nitrogen, but in fact, yttrium barium copper oxide can directly reach the superconducting state.
The application range of copper-oxide is not wide, and now more and more niobium-titanium alloys are used as superconductors."
"This is because the critical current density of yttrium barium copper oxide polycrystalline is too low unless we can prepare it in single crystal form."
"But unfortunately, the cost of preparing single crystal forms is a bit too high, so we have to give up on this."
"Um."
Listening to Lin Xiao's narration, Zhao Xian nodded, he knew all this, and then said: "However, there is another reason, that is, yttrium barium copper oxide is too brittle and cannot have as good properties as copper or niobium titanium alloy.
Toughness, in this case we can’t use it to make wires, which is very inconvenient.”
Lin Xiao nodded slightly, "Yes, so its range of use is relatively short."
Zhao Xian nodded, but then asked doubtfully, "But what does this have to do with changing the structure you said? Do you want to change the structure of YBCO?"
Lin Xiao nodded, and then started to operate the computer without any nonsense.
"You should have soft armor that simulates material superconductivity on your computer... Well, I found it, QE."
Then he opened the QE software directly, entered the software interface, and then started using the software.
Seeing Lin Xiao's skillful operation, Zhao Xian couldn't help but feel surprised.
Generally speaking, when they study superconductors, they will also use computational materials methods to conduct auxiliary research, and there are also some software that can simulate this.
Of course, Zhao Xian is not very good at this aspect. After all, he is already old. He has not systematically studied the new field of computational materials science, that is, he only has a relatively good understanding of it. Of course, his comparison
Understanding means being able to write a few doctoral theses in this area at will. After all, for an academician like him, his learning ability is of course very strong.
However, watching Lin Xiao's operation at this time, he suddenly remembered that before Lin Xiao proposed the electronic topological bonding theory, he also proposed a theory called Lin's bonding mechanism. This Lin's bonding mechanism,
But it also has a lot to do with computational materials science.
Thinking of this, Zhao Xian couldn't help but sigh, no wonder people outside say that Lin Xiao is an all-powerful scientist. This statement is true.
He looked at Lin Xiao's operation again, but at this time he couldn't help but was stunned: "Huh? What are you doing? Yttrium barium copper oxygen is not the parameter, right?"
He suddenly saw that Lin Xiao was inputting various data about the simulated test materials, but these data were somewhat different from the original yttrium barium copper oxide, and there were some differences in the crystal structure.
Lin Xiao smiled and said, "I want to do an experiment."
"experiment?"
"Well, this experiment will be carried out on the software for the time being. If the results I expect can be achieved, the Dingguang Research Institute will probably establish a superconducting laboratory in the future."
"Oh? Don't come here to poach our people then." Zhao Xian raised his eyebrows and said, "There are already very few people in our laboratory."
Lin Xiao smiled and said: "I can't give you a guarantee on this issue for the time being."
"Good guy, are you telling me nakedly that you plan to poach people from our laboratory?" Zhao Xian immediately laughed and cursed, but then he shook his head and said: "Forget it, whatever you want, I guess it will be fast anyway.
I have retired, and there are fewer and fewer people studying superconductors now. If you can rekindle young people’s interest in superconductors, then that’s up to you.”
Lin Xiao was silent for a moment, then turned around and continued to enter other parameters, and asked at the same time: "You said, if room temperature superconductors are really developed, will everyone who has studied superconductors in the past be unemployed?"
"This..." Zhao Xian was stunned, not expecting Lin Xiao to ask about this matter.
"Well, I don't know. I have never thought about this before. After all, I never thought that I would see room temperature superconductors appear in my lifetime - oh, I have to add the condition of normal pressure, but
No matter what, even if normal temperature and normal pressure superconductors appear, the cost of preparation must be very high when they first appear. Then people can study how to reduce the cost of preparation. This will probably take several decades, and computers will be from scratch.
There was a span of several decades between the emergence of personal computers and the emergence of personal computers.”
"In addition, taking a step further, even if this kind of normal temperature and normal pressure superconductor suddenly appears, and the preparation cost can be used for civilian use, then compared with the significance of this superconductor to human society, even if there are many
People have lost their jobs, but the work is still in the future.”
Listening to Zhao Xian's answer, Lin Xiao nodded.
He once told Kong Huaan that his greatest ideal is to realize communism, and realizing communism first requires extremely advanced science and technology, and room-temperature superconductors can definitely be regarded as necessary technologies for this kind of society.
The transmission of energy with almost no loss is of great significance to a society. It means a great improvement in productivity and a great development of production levels.
This is why Lin Xiao suddenly became interested in this thing.
However, there is no point in talking about this now, so it is better to solve the problem in front of him first, so he no longer thinks about it, puts his eyes back on the computer in front of him, and continues to operate.
When Zhao Xian saw this, he asked, "You haven't said what experiments you want to conduct yet."
"Oh, this." Lin Xiao replied: "This is an experiment about Cooper pairs."
"Cooper right?"
Zhao Xiansheng was confused. Cooper pairs are a thing in BCS theory that explain the behavior of electrons in low-temperature superconductors. That is to say, in superconductors, electrons form a Cooper pair in pairs, and then they can achieve superconducting properties.
That is, the unhindered flow of electrons in a conductor.
However, in high-temperature superconductors, physicists are still not sure whether Cooper pairs are responsible for the superconducting properties, but in the mainstream view, people still believe that Cooper pairs are the main reason for the formation of superconductivity.
Now Lin Xiao plans to conduct experiments on Cooper pairs. Could it be, "Do you think Cooper pairs are also the main cause of superconductivity in high-temperature superconductors?"
Lin Xiao replied: "Why can't you think so? Of course, I didn't say that Cooper pairs are the final explanation of the superconducting mechanism."
"However, I believe that all physicists agree with me that the ultimate fully unified superconducting mechanism must be able to explain why we can no longer easily observe the existence of Cooper pairs in high-temperature superconductors."
"My experiment is actually to try to find whether there are Cooper pairs in yttrium barium copper oxide. This new structure of yttrium barium copper oxide is an equivalent topological change that I made based on the electronic topological bonding theory.
, and then let’s take a look at the simulation results of the software. If my guess is correct, although other properties of the yttrium barium copper oxide under this new structure have not changed much, the critical current density should be higher.
big change."
"Oh?" Hearing what Lin Xiao said, Zhao Xian immediately became interested. Lin Xiao actually used the electronic topological bonding theory to study?
The original yttrium-barium-copper-oxide crystal structure was even directly transformed into an equivalent topology.
The electronic topological bonding theory has this effect. It can easily calculate the equivalent structure of a crystal structure. The two structures are different, but they can be completely regarded as equivalent.
However, what made Zhao Xian a little confused was: "I didn't even look at your calculations. How can you be sure that the data you entered is correct?"
Regarding this question, Lin Xiao said matter-of-factly: "Mental arithmetic, this kind of calculation is not very complicated, just do mental arithmetic."
Zhao Xian looked at Lin Xiao and saw that Lin Xiao had entered more than 20 data, and there seemed to be no pauses. He thought to himself, it would be strange if he believed it. Is this something that normal mental arithmetic can calculate?
Isn't it complicated to have more than twenty data? Moreover, Lin Xiao seemed to input it without thinking. Zhao Xian asked himself that he couldn't do it. As for anyone else, I'm afraid he couldn't do it. It was probably the youngest in front of him.
Only a Fields Medal winner could do it.
And now we have only entered more than twenty data. Looking at the situation later, at least dozens more data will need to be entered. After all, the chemical formula of yttrium barium copper oxide contains thirteen
Atoms, plus other data, dozens of data are still relatively small.
So he quietly watched Lin Xiao's input, hoping that he would stop and think.
Zhao Xian even made a bet with himself that he would drink an extra bowl of bean juice for breakfast tomorrow.
In the end, it was a pity that after Lin Xiao entered all the data, he did not think about it for even half a minute. It seemed that he calculated the value of the next data while entering the previous data.
It seems that tomorrow morning I can only drink one more bowl of bean juice with tears in my eyes.
A sad smile appeared on Zhao Xian's face.
"Have you finished typing?"
Lin Xiao nodded: "It's over."
Then, he pressed Enter, and the software immediately started calculating the data, and a progress bar appeared.
Both of them looked at the progress bar expectantly, waiting for the moment it reached 100%.
In this way, time passed quickly. Finally, the progress bar reached 100%. Then, the interface jumped and the results came out.
Looking at the results, Zhao Xian was immediately shocked: "The critical current density... actually increased! Why? According to the electron topological bonding theory, isn't this an equivalent topological transformation? Why does this happen?
"
Lin Xiao did not speak, but took a pen and notebook from the side, and then began to calculate on it.
"Add two electrons to the Fermi Sea surface of an N-electron system. These two electrons do not interact with the electrons in the Fermi Sea, but there is a mutual attraction potential between the two electrons. These two electrons obey the Schrödinger equation.
"
【-h/(2m)(▽1+▽2)ψ……】
[Finally, we can find: ε=2hωD/(1-e^2/vz)≌-2hωDe^(-2/vz)]
Writing this, Lin Xiao said: "Now, I can believe that the cause of this situation must be the appearance of a large number of electron pairs. I can even make a bold inference that these electron pairs, and Cooper
The pairs are closely related, and they are even Cooper pairs!"
Zhao Xian looked down at Lin Xiao's proof process with shock on his face.
He had no idea that Lin Xiao would come to such an astonishing conclusion after just a few random attempts.
Once this matter is announced, I believe the entire superconducting world will be shocked.
Because Lin Xiao’s proof is equivalent to saying that the Cooper pair still plays an extremely important role in the high-temperature superconductor of yttrium barium copper oxide!
In other words, he has brought an important result to the high-temperature superconducting mechanism that the superconducting community has been pursuing!
