The yttrium-barium-copper-oxide superconducting material that Chen Zongze and his team are currently studying is called copper-based metamaterial. The basic design idea of this type of material is to dope the copper oxide matrix with other elements, such as yttrium, samarium, and neodymium.
Wait. As soon as the copper-based superconducting material came out, it quickly broke through the boiling point of liquid nitrogen of 77K, triggering a boom in superconducting applications in the liquid nitrogen temperature region.
However, the fatal weakness of copper-based superconductors is that copper oxide is essentially a ceramic material, lacking toughness and ductility, and has extremely poor mechanical properties. This weakness makes the preparation of copper-based superconducting materials quite difficult, especially
When it is to be made into linear or strip-shaped materials, other tough materials must be used as substrates.
In addition, although the maximum critical temperature of copper-based superconducting materials has reached 135K under normal pressure and 164K under high pressure conditions, it is still far from the room temperature requirement of about 300K. The most important thing is that scientists have theoretically
Research believes that 164k may be close to the highest theoretical upper limit of copper-based superconducting materials. In other words, despite the rapid development of copper-based superconducting, if the ultimate goal is room temperature superconducting, then copper-based materials can already be considered for washing
Fell asleep.
In addition to copper-based materials, scientists have also studied magnesium diboride and organic superconducting materials, but progress has been very slow, especially the failure to form a breakthrough in theory. By the first few years of the 21st century, superconducting research had
It seems that we have entered a dead end and it is difficult to find a new direction.
In early 2008, Japan's Hideo Nishino research group reported that superconductivity of 26k was observed in fluorine-doped lanthanum iron arsenic compounds. Chinese scientists who had long explored new superconductors in similar structural systems got the news and quickly used samarium.
Lanthanum in the replacement materials of cerium, praseodymium, neodymium, gadolinium and other elements broke through the "MacMillan limit" of 40k in just a few dozen days, thus opening the door to iron-based superconducting materials.
The discovery of iron-based superconducting materials is another revolutionary discovery in superconducting research. Although iron-based superconducting materials had not broken through the 77k liquid nitrogen temperature zone until the time before Qin Hai crossed. But scientists believe that,
This is just a matter of time. Future room temperature superconducting materials are very likely to be born from iron-based superconducting materials.
Qin Hai is very familiar with this period of scientific history. Now that he has a chance to do it again, he will not refuse to give the honor of discovering iron-based superconducting materials to his family. Moreover, he hopes to be able to do it in his own hands.
, raising the critical temperature of iron-based superconductivity all the way to room temperature, thereby finally solving the century-old problem of room temperature superconductivity.
Hearing Qin Hai say the words "iron-based superconductivity", Ning Jing frowned and said, "Qin Hai, you are totally wrong this time. According to the BCS superconducting theory, it is impossible for a material to be magnetic.
It has high-temperature superconductivity. Iron is a typical magnetic element. When we design superconducting materials, we will try to avoid the presence of iron elements."
Qin Hai smiled and said: "Who told you that the bcs superconducting theory must be correct? In other words, who told you that there is only one superconducting mechanism in nature? I won't tell you how I considered this principle, but
I might suggest that you try doping the iron-arsenic compound with different elements, and I suspect you'll be able to observe superconducting properties."
Within a few years after the concept of iron-based superconductivity was proposed, scientists discovered hundreds of iron-based superconductors, and some even estimated that the number of members of the iron-based superconducting family could reach more than 3,000. In this case, Qin Hai
There is no need to directly tell Jingjing all the experimental ideas of later Japanese people, he only needs to point out this direction. Even if Jingjing hits one of them by mistake, he will definitely hit one of them.
"That's weird. Brother, why are you so confident?" Qin Shan turned to look at her brother and asked curiously. When she was in middle school, she only knew that although this brother had not gone to high school, he was familiar with high school knowledge and could give her
He Jingjing gave a lot of precise guidance. After going to college, she discovered that her brother was far from just being outstanding in his homework. He knew almost everything about the development trends of material science and technology, and he could write excellent articles just by giving you an idea.
.If the guidance in high school can be explained by seriousness in study, the guidance on scientific research now can only be described as unpredictable.
Fortunately, both Qin Shan and Jing Jing, under the subtle influence of Qin Hai, have become somewhat numb to this kind of miracle. Occasionally they have doubts, and they will put them aside because they become accustomed to them.
Regarding Qin Hai's instructions, their common reaction now is to quickly record it and then work hard in the direction Qin Hai pointed out. They know that there will definitely be a big fish in this direction.
"Iron-based superconductivity..." Ning Jing slapped his forehead and said, "Is this related to electron scattering on the hole-electron Fermi surface? Teacher Chen actually mentioned such a conjecture at an academic seminar.
I just don’t have time to do experiments. Qin Hai, you didn’t think so after listening to Teacher Chen’s report, right?”
"I'm afraid Teacher Chen is not the only one who has this kind of conjecture." Qin Hai said with a smile, what kind of empty holes did Ning Jing talk about, Fermi surface, etc. Qin Hai only knew it but didn't know why.
The secret was revealed. He waved his hand and said: "Don't make things difficult for me, a technical school student, with this theoretical issue. You should seize the time to do experiments. If you have any theoretical problems, go to Teacher Chen to discuss it. However, you can discuss this idea
But you have to keep it secret first, otherwise if it leaks out and other people know about it, you won’t be able to gain originality.”
"Didn't you ask us to do applied research? How can I have time to do these experiments?" Ning Jing laughed and led Qin Hai's army.
Qin Hai said seriously: "Doing applied research is other people's business. You are also the major shareholder of the research center after all. Do you still need to do such a non-technical thing?"
If Zhang Shengying heard these words, she would probably spit out a mouthful of old blood three feet away. As a great professor, she was forced to do applied research, otherwise she would not be able to receive experimental materials. Ning Jing, a first-year direct Ph.D.
You can actually enjoy the benefits of not having to do applications and concentrate on theory. Is there any justice in this world?
Jing Jing obviously also thought of this, she said: "I don't dare, it's my classmates' turn to criticize me later."
Qin Haidao: "This is not difficult. I just tell Teacher Chen and let him arrange for you to go in this new direction. After the article is written, let Teacher Chen be the first author and you be the corresponding author, and the benefits will be equally divided.
He won't disagree."
"If this experiment can really be done, it will completely subvert the traditional superconducting theory. There is really hope for such an article in Nature. If you tell Teacher Chen like this, he will definitely agree and even
The strongest manpower has been mobilized to work in this direction." Ning Jing said.
Qin Haidao: "This is not possible. The honor of discovering iron-based superconductors must be yours and cannot be taken away by others. Don't worry, it will not be easy for others to steal it. The preparation of iron-based materials is much more difficult than that of copper-based materials. The cost
It’s much bigger too, I don’t agree, others can’t get so much funding for sample preparation, so just go ahead and do it boldly, the glory belongs to tranquility, I’m optimistic about you.”
Jing Jing said hypocritically: "Since you are so sure, why don't you do it yourself? Don't you suffer a loss by giving me such a good idea?"
Qin Shan curled her lips and sneered: "Xiao Jing, stop being so pretentious. My brother's is yours, isn't it? Why are you pretending in front of me?"
"Xiaoshan, you don't want to eat apples anymore, do you?" Ning Jing threatened, holding up a half-peeled apple, but her eyes secretly glanced at Qin Hai.
Regarding the relationship between her and Qin Hai, Qin Shan, Qin Ling, and her own brother Ning Mo have discussed it countless times, half jokingly and half seriously, but Qin Hai has never let go of the big tree.
By the way, I really don’t know what he was thinking.
In fact, Qin Hai had already been attracted to this beautiful and cheerful girl when he first saw Jing Jing. Otherwise, he would not have been so sticky and confused with Jing Jing in the following years.
What I don’t know is that the key point is that Qin Hai, as a time traveler, was nearly 30 years old in his previous life. When he first met Ning Jing, Ning Jing was only 16 years old. He was considered a typical green apple. How could Qin Hai be able to do this?
mouth.
It is such a psychological disorder that has accompanied Qin Hai for many years. Now that Ning Jing has graduated from college and the apples have turned an attractive red color, Qin Hai feels that he can accept this temptation. A few days ago, he went to the Superconducting Research Center
, that Senior Brother Hou said that many dandies driving luxury cars come to harass Jingjing every day, which makes Qin Hai feel a sense of crisis. The flowers are in bloom, is it time to confess to Jingjing?
"Xiao Jing, Xiao Shan didn't tell me, but I forgot about it. I heard from your senior brother Hou that during this period, there are a lot of people driving luxury cars to the research center to look for you. What is going on?" Qin Hai
asked leisurely.
Jing Jing blushed, took a sip, and said: "Aren't they all tycoons who think they are rich? Many of them are seniors who graduated from our school in the past. I don't know how they heard my name and drove away.
They came here to make friends with me. Some said they would take me to dinner, some said they wanted to invite me to a movie, and some were already older men in their 30s, and they did not think they were shabby.
By the way, there is another person who makes me laugh to death. He is fatter than my brother, and he said to me that day: Junior Sister Ning, where can you find a talented young man like me?"
Having said this, she stood up and gestured to the man's waistline, and then she and Qin Shan laughed until tears ran down their cheeks.
"Your circle is really chaotic..." Qin Hai also commented with a smile, and then asked: "Among these people, there is no one you can like?"
"What do you think?" Jing Jing glared at Qin Hai and asked, "Do you particularly hope that I can find someone among them that you can like?" (To be continued, please search Piao Tian Literature for more novel updates. Good update faster!