When it comes to blockade and stuck neck, I have the impression that others are always stuck in China's neck.
How much will China card the necks of other countries?
The laser crystal technology that stuck the neck of the United States was discovered in China as early as 1990.
90 years? The nineties?
I guess many people will be a little surprised.
After all, after the reform and opening up, Chinese people have opened their eyes to the world, and almost all of them are more advanced than China.
Otherwise, it would not be the time of the global division of labor, and China will be divided into the most basic industrial links.
What does that mean?
For example, in the case of steel, China is responsible for smelting iron ore into crude steel, and the steel ingots are exported to Japan.
Japan then refined this piece of crude steel, turned it into special steel, and then sold it to China.
There is no way that the technology is not good, so you can only start from the most basic.
The nineties? Can the technology work?
Actually, right? If many technologies start from the same starting line, China's technology is really not bad, and it can even lead the world.
But if you want to talk about people running for decades or even hundreds of years, and China will follow suit, it will definitely fall behind, and if you want to catch up, it will take a certain amount of time, and even overtake in corners.
And the crystal technology that I want to talk about today has done better because it has opened up another track, and the Chinese have run it out by themselves.
So that the United States has lagged behind for fifteen years, and has been chasing for fifteen years, and even China has imposed a technological blockade on the United States.
Want it?
Yes!
Hehe! Don't sell!
That's what it simply is.
So let's talk about this issue today.
Crystal development in China
This laser crystal is actually the third generation of China's products.
Speaking of which, explain a few concepts.
Laser crystals, lasers are understood, but what about crystals?
Crystal is a very important functional material, which can produce some physical properties such as light, electricity, magnetism, force, heat, etc., and even a material carrier used in mutual conversion.
As soon as you hear this concept, you know that crystals are definitely an extremely important material in today's life.
Indeed, for example, the four major inventions that came down in the twentieth century, semiconductors, integrated circuits, that is, computers, lasers, and atomic energy, would basically stop if they left crystals.
To put it simply, the world's first semiconductor was fabricated on a germanium wafer.
And integrated circuits are all known to be done on a single silicon crystal.
What about the first laser? It was born on a ruby crystal.
One of the paths of today's artificial sun, inertial confinement fusion, also uses crystallography.
Therefore, mastering crystal technology is mastering the key to many devices.
So we have to start from the beginning about crystals.
It is said that as early as the sixties of the last century, China began to devote a lot of energy to research.
The team was led by the famous Chinese chemist Lu Jiaxi, and the situation at that time can be said to be very bad.
Because in this field, foreign countries have already started, and people have decades of technology accumulation, and it is almost impossible for China to catch up.
Therefore, it is the old road, starting from imitation, but imitation also has to draw bones and marrow to draw spirit.
Just looking at imitation will also hit a bottleneck.
At this time, Lu Jiaxi sent Chen Chuangtian to carry out theoretical calculations.
Theory is very powerful, like a light in scientific research, use it to illuminate the fog ahead, not let you get lost in the darkness of this field, and walk on the right path.
Then Chen Chuangtian also paid off his efforts, using the ability of grinding an iron pestle into embroidery needles, and finally came up with a set of theories in 1976, called crystal nonlinear optical effect - anionic group theory.
This name is too long, and the average person who looks long frowns when he sees it.
Then the principle is not explained, after all, it is scratching your head when you look at it, involving ultraviolet rays, visible light, near-infrared bands and so on.
In a word, Chen Chuangtian's set of theories is completely different from his foreign counterparts.
This is equivalent to a field of track, which has been opened up abroad for decades, wide and good, and the visibility is not bad.
It is easy to run along this track, but it will not be you who will be in the lead, but always those who run in front.
As a result, Chen Chuangtian directly opened a new track next to him, and the Chinese used this track to run, which was a little more difficult, but the Chinese were the leaders of this track.
That's the truth.
So now Chen Chuangtian's anionic group theory has become a very important guiding theory in crystal research all over the world, it is like a lighthouse to tell the researchers who come in, where is the location, you have to watch this set of theories move forward.
In the end, the Chinese first obtained the first crystal in this field, called low-temperature phase metaborate barium crystal.
In 1986, at the 14th International Conference on Quantum Electronics and Laser Optoelectronics held in San Francisco, China, China came up with this low-temperature barium metaborate crystal.
At that time, the scientists attending the meeting were in an uproar, especially after listening to the entire optical performance data, all the scientists were even more surprised.
To what extent?
Chen Chuangtian stepped down from the podium and was about to leave the venue.
As a result, half of the more than 200 scientists in this field followed Chen Chuangtian.
They were not interested in the following meeting, so they wanted to know more about the details of this crystal.
This led to an unexpected interruption of the meeting.
From this reaction, we can see how powerful this crystal developed under Chen Chuangtian's theory is.
And this crystal, when it is mentioned in the future, will say a Chinese brand crystal.
Is that the end of it?
No, not at all.
The characteristic of the Chinese is that there is a step of development, so is there any further development?
On the way to scientific research, I hit a roadblock, and there is no one in front of me, so I have to find another one and hit it again.
So after Chen Chuangtian went back, he started a new research and development.
Not long after, another crystal was taken out, called lithium triborate crystal.
Ordinary people don't feel much when they look at this name, at most they will say, ah, so fast?
But professionals don't see it that way, such as Emer of the Livermore Laboratory in the United States, when he met Chen Chuangtian, he asked:
From the point of view of whether the crystals are easy to grow, what grows should be lithium tetraborate, not lithium triborate.
Why? Your experiments will grow lithium triborate?
What did Chen Chuangtian say?
The answer is very simple, Chinese researchers use the anionic group theory as a guide, so before studying what kind of lithium borate needs to grow, they used this theory to make a calculation.
Then a result was obtained, lithium triborate is better than lithium tetraborate, so Chinese researchers let it grow lithium triborate.
It's as simple as that.
Later, it took almost ten years to study the third generation of crystals - potassium fluoroborobellium crystals.
It should be noted here that there are currently four kinds of nonlinear optical crystals in the world, only one of which was invented by DuPont in the United States, and the other three were invented by China under Chen Chuangtian's anionic group theory.
Although there are now three types of these crystals in China, there are actually several series in China, with a total of more than 20 varieties.
Technological blockade issues.
From the beginning of the eighties to the early nineties of the last century, nonlinear optical crystals, China's low-temperature phase barium metaborate basically solved a scientific problem, the output of ultraviolet harmonic light effective power.
At this time, there is another wall standing in front of all scientists - deep ultraviolet, that is, the wavelength of the laser is shorter than 200 nanometers.
It doesn't matter if you don't understand the name of many fields of science, the key is to know what it means.
If the deep ultraviolet breaks through, this is amazing, which is equivalent to getting the key to precision and practical deep ultraviolet all-solid-state laser detection.
directly stood on the commanding heights of this field.
So if you want to produce deep ultraviolet, this is inseparable from the carrier of crystals, and you must also find crystals suitable for deep ultraviolet.
Faced with this problem, many scientists have taken up arms and started to challenge.
Chen Chuangtian also led the team and launched a challenge with the anionic group theory he founded.
According to the old rules, first calculate, then look at the results of the calculations and think, and finally choose the direction and study it in one go.
This is the later potassium fluoroboboronium beryllium crystal, the third-generation crystal developed in China, using this crystal, you can directly break the 200 nanometer laser barrier and blow away a solid stone in the laser world.
Is the stuff good?
Well, of course, the highest-end crystals can emit the highest-end lasers.
So in 2007, potassium fluoroboboronium beryllium crystals were banned from being exported.
It can be said that this crystal has also become the first thing China said no to the United States in the high-tech field.
Therefore, if you can stand at the forefront of science, you can say no to others.
In 2008, China launched the deep ultraviolet solid-state laser source frontier equipment project, and developed eight deep ultraviolet laser scientific research equipment in one go.
Now relying on fluoroboramonium beryllium crystals, a new industrial chain has been formed, from crystal manufacturing, to the design of light sources, to the research and development of equipment, and then to industrialization, which can be described as a one-stop.
The most noteworthy thing is that when interviewing Chen Chuangtian, Chen Chuangtian said something like this:
"I find it difficult for others to replicate me today."
It's so heroic.
Finally, a few more vignettes
In fact, Chen Chuangtian's anionic group theory is really a path that he has no choice to take.
What's going on?
At that time, when the ultraviolet spectral region was studied, there was only one material—urea.
This material is easy to deliquescent and difficult to use, which led to the idea of studying nonlinear optical crystals in the ultraviolet spectral region.
With this idea, I began to look for a suitable material and found one, but the light transmission of this material is not very good.
Then I searched for another two months before I found a group and developed it on this basis.
This led to the great development of nonlinear laser crystals.