In the conference room, Xu Chuan took the notebook from Fan Pengyue's hand and flipped through the data inside.

The researcher who discovered the ultra-low temperature superconducting copper-carbon-silver composite material is called 'Song Wenbai', a professor who was recruited from Wuli University, and his main research field was materials chemistry.

This time, Professor Song was able to explore ultra-low temperature superconducting materials, half of which relied on experience, and half of which relied on luck.

He did not follow the powder metallurgy method of traditional materials science, nor did he take the high-temperature and high-pressure synthesis method commonly used to study superconductor materials to study copper-carbon-silver composite superconducting materials, but adopted the development route of nanomaterial preparation and molecular modification.

He first prepared copper-carbon-silver composites by nanomeans, and then manipulated and adjusted the fine atomic structure by vapor deposition.

Compared with the powder metallurgy method for the conventional preparation of copper-carbon-silver composites, this new method solves the problem that the interface between copper and carbon is not firmly bonded and there are a large number of holes in the composites.

Compared with the high-temperature and high-pressure superconductor research method, it also avoids the disadvantage that copper atoms and carbon atoms do not react even at high temperatures, and the wettability is extremely poor.

I have to say that Wuli University, which can rank among the top five universities in China in the field of materials research, still has some ability.

A professor of materials chemistry who is above average, not a top level, has sufficient experience and coping methods in the research and development of new materials.

If there is a disadvantage, it is that in the process of deposition of 2D thin films, binders, even in small amounts, are used, which to a certain extent destroys the purity of the copper-carbon-silver composite itself.

This doesn't just mean that it needs a lower temperature to allow the film material to reach the superconducting energy gap. It also means that the properties of the material itself are greatly reduced.

"It's kind of interesting, call this Professor Song, ask him if he has time now, if so, ask him to come over, I have some questions I want to consult him."

After flipping through the information in the computer, Xu Chuan raised his head with interest, tapped his fingers lightly on the table, and said to Fan Pengyue.

To be honest, the value of this ultra-low temperature superconducting copper-carbon-silver composite material itself is actually not so great.

First of all, the material that Professor Song has studied is a two-dimensional thin film structure, and it is still very difficult to process it into a superconducting material of wire or other shapes.

The second is to achieve superconductivity at a temperature of 43.5K (about -230 degrees Celsius), which has already existed outside.

For example, CERN's Large Strong Particle Collider.

Accelerating particles requires a super-strong magnetic field, and a strong magnetic field requires superconducting materials to reach its limits.

The LHC particle collider uses a niobium-tin alloy, which has been cooled by liquid helium to be superconducting in atmospheric environments and can be mass-produced.

Aside from low-temperature superconductivity, high-temperature superconductivity has actually been studied for a long time.

As early as 1987, scientists from China, China, small island countries and other countries found that 'barium-yttrium-copper oxide' has Tc in the liquid nitrogen temperature region, thus having superconductivity.

(Tc stands for Critical Temperature, which is the temperature at which a material transitions from a normal state to a superconducting state.) For example, when the temperature of mercury is slightly lower than 4.2K, the resistance of mercury suddenly disappears, showing a superconducting state, so the Tc of mercury is 4.2K, about minus 268.95 degrees Celsius. ）

However, due to the fact that copper oxide superconductors are like brittle ceramic materials, you can't draw them into thin wires, coupled with the high manufacturing cost and the failure of the slightest impurity pollution, high-temperature superconductors have not been able to be applied to industry.

Therefore, the temperature superconductivity of 43.5K alone does not have much practical value.

Not only does it need liquid helium freezing to be superconductive, but it can't be industrially produced.

However, he found something very interesting in this material.

If we can figure it out, we may be able to explain the superconducting principles of high-temperature superconducting materials from another perspective.

To know the high-temperature superconducting basis of superconducting materials, let alone the beginning of 2020, even in more than ten years, no real explanation will be found in later generations.

Even if he researched room-temperature superconducting materials in later generations, he failed to explain the reason for the existence of room-temperature and high-temperature superconductors.

In other fields, this is almost impossible or extremely difficult.

Before the theory is formed, how can the actual results be made?

However, in the field of materials science, experiments that happen to come out without theory are nothing more ordinary.

Many of the materials used in society today are actually based on results first, and then research results to obtain theories.

If the superconducting basis of high-temperature superconducting materials can be clearly explained, this will definitely be a huge improvement for the development of superconducting materials.

Fan Pengyue nodded, took out his mobile phone from his pocket and made a call, asked for a while and hung up the phone.

I didn't have to wait long before there was a knock on the door outside the conference room.

Xu Chuan opened his mouth and said, "Please come in." ”

Immediately, the door opened, and a middle-aged man with gold-rimmed glasses walked in.

"Mr. Fan, are you looking for me?"

Song Wenbai walked in and asked, but his eyes fell on Xu Chuan, who was sitting at the desk.

The familiar figure made him involuntarily stunned for a moment, and asked in disbelief: "You are Academician Xu?" ”

When the Chuanhai Materials Research Institute dug him, he knew that the real owner behind this laboratory was the famous Professor Xu Chuanxu.

He recognized Xu Chuan, but he was a little skeptical that it was true.

Because from the time he joined the company to the present, let alone him, most of the people in the Chuanhai Materials Research Institute have never met this real boss.

So even if you see a real person, you will wonder if you are wrong.

On the other side, Fan Pengyue looked at Xu Chuan and said with a smile: "You said that you, you have been in charge of the shopkeeper for a long time, and the employees of the company don't know you anymore." ”

Xu Chuan ignored Fan Pengyue, he smiled at Song Bai and said, "It's me." Professor Song, please take a seat, I came to you this time, mainly because I want to consult some questions. ”

Song Wenbai walked over quickly and asked with some nervousness, "You say." ”

Although he is much older than the one in front of him, there is a huge difference between the two in terms of knowledge and status.

Academician-level giants, there are only four in the entire Wuli University, although he has seen and communicated, but it is the first time that this kind of academician giant has become his top boss.

Moreover, this is still in the private enterprise, not in the school, and the leader's power over his subordinates is greater, and the pressure on him is also greater.

Of course, if you grasp the opportunity, especially the Chuanhai Materials Research Institute, which has just begun to expand, the future road will be very bright.

He is almost fifty years old this year, and his own academic level is there, although he is not weak, but he is not top-notch, so the prospect of promotion on the Wuli side has almost reached the top.

And in a new environment, you may be able to go a little further. This is also the reason why he was able to be poached, not only for money, but also for the hope of promotion.

Xu Chuan didn't pay much attention to these things, he connected the computer on his desk to the virtual projection, and opened the research data of ultra-low temperature superconducting copper-carbon-silver composite materials.

"I have some questions about the ultra-low temperature superconducting copper-carbon-silver composite materials you have developed."

"First of all, about the X-ray diffraction analysis data, through X-ray research, there is a structural phase transition process from orthorhombic crystal to tetragonal crystal in the sample at X≈0.04, and the protocellular volume increases with the increase of copper composition."

"The zero resistance temperature measured by the R-T curve will decrease rapidly with the increase of copper composition, until it decreases below the temperature of 50 K, and the zero resistance temperature decreases with the increase of X, and there is no sudden change at the phase transition point of the structure."

"What do you think about that?"

There is no analysis answer to this question in the data given to him by Fan Pengyue, which means that the current analysis results have not been made.

If you want to know, it is the fastest to ask the person in charge of the experiment directly.

Song Wenbai thought for a moment and said: "According to my speculation, this should be the effect of the doping of elements such as the adhesive on the copper-carbon-silver composite material, and the electronic doping of the adhesive will cause its lattice coefficient to change. ”

"When I was at Wuli University, I studied the effect of hole doping on the electronic structure, and under the external pressure system, the magnetism was gradually suppressed by the many-body effect of electrons in the strongly correlated system."

"This may be the reason why the zero resistance temperature decreases with the increase of X when the temperature is reduced below 50 K, and there is no sudden change at the phase transition point of the structure."

Listening to Song Wenbai's explanation, Xu Chuan's fingers tapped on the table, and his mind fell into deep thought.

Effect of hole doping on electronic structure and lattice coefficient?

If he remembers correctly, in his previous life when he was researching copper-carbon-silver composite superconducting materials, he did not study copper-carbon-silver composite materials at the beginning, but copper-silver oxide nanomaterials.

Because oxidizing materials are recognized as the most promising ones to break through the limits of high-temperature superconductivity.

Later, the reason why he replaced oxygen with carbon was actually caused by an accidental experimental accident.

The reason why oxide superconductors have become mainstream is not only because they can break the limitations of ultra-low temperature superconductivity, but also because copper oxide high temperature superconductors also exhibit many strange properties.

For example, the superconducting phase has d-wave pairing symmetry, which is different from the s-wave symmetry of conventional superconductors.

For example, the parent material has an antiferromagnetic Mott insulating phase, and there are pseudo-energy gaps and Fermi arcs in the underdoped region.

Today, Song Wenbai's words have brought him a new inspiration, and the key that he has not figured out before may be answered.

If the original copper-silver oxide nanomaterials are regarded as superconductors, perhaps the accidental doping of carbon into the original materials may break the key to the critical temperature of Tc.

Perhaps, he can find the mechanism of superconductivity formation of copper oxide high-temperature superconductors.

If successful, this will definitely be the biggest breakthrough ever for high-temperature superconducting materials!

And with this set of theories, he can logically develop superconducting materials at the fastest speed.

It's just that now he needs more data and information to verify what he has in mind!

PS: Make up for yesterday's second chapter, ask for a monthly pass

(End of chapter)