Chapter 136 The experiment failed?
In this formula, △(k) and △(k') respectively represent the energy gap sizes of the electrons participating in paired scattering at the wave vectors k and k' before and after scattering. Vk, k' are then Represents the scattering matrix element in the electron pair scattering process.
“For pairing caused by the interaction between electrons, Vk, k' must be positive values, so △(k) and △(k') must also have opposite signs...that is to say, the electrons are pairing Before and after scattering, the sign of the energy gap at the momentum position must be opposite..."
After continuous analysis, Ning Chen calculated whether various materials in this system have superconducting properties and possible superconducting properties. critical temperature.
After some analysis, Ning Chen quickly selected an ideal superconducting structure.
"The theoretical critical temperature of superconducting is 55K... If it can really be realized, this temperature will already be a new record for iron-based superconductors."
The new experimental direction has been determined, and Ning Chen is already looking forward to future experiments. got up.
......
In the following days, Ning Chen continued to follow this idea and conduct research on iron-based superconductivity.
This new substance is not easy to synthesize. Ning Chen has maintained a relatively peaceful attitude. After all, his previous project has gone very smoothly. It is normal to encounter some obstacles. .
After dinner, Ning Chen saw the message sent by Song Xiyun.
"Ning Chen, after buying new running shoes, have you tried running?"
Seeing the message sent by Song Xiyun, Ning Chen realized that he and Song Xiyun had The promised night running project was accidentally delayed again.
“Let’s do a trial run tonight, or the same time?”
“Well, that’s settled then.”
Ning Chen knows that scientific research is a very long road, and if he wants to achieve more results, he must not just settle for one day.
Many outstanding scientific researchers also maintain very regular exercise habits. This allows them to have strong enough physical fitness to maintain daily high-intensity research work.
Ning Chen naturally wants to continue his scientific research work. Even if he is old, Ning Chen also hopes that he can continue to stick to his scientific research position instead of just fishing and playing cards every day. A very relaxed but empty life.
At nine o'clock in the evening, Ning Chen came to the playground on time, put on his headphones, and called Song Xiyun.
Before this, Ning Chen had already purchased a national call package of 3,000 minutes per month in advance to ensure that he could always be in contact with Song Xiyun while running.
In less than two seconds, the other side of the phone was connected.
"Song Xiyun, I'm already at the playground, where are you?"
"I'm here too, shall we start now?"
"Well, let's start."
After Ning Chen gave the start signal, Ning Chen and Song Xiyun started running from their respective playgrounds at the same time.
Although the distance between the two people was 700 kilometers at this time, because they could feel each other's presence through the headphones, they both felt as if the other person was right next to them.
At the beginning, Ning Chen’s body was not in good condition because he had not run for a while.
But as he ran, Ning Chen's body gradually began to adapt to this intensity.
I don’t know if it was because of running at night with Song Xiyun in this way, Ning Chen felt that his body was full of strength.
Ning Chen got back the feeling he had when running every night at Shuimu University.
"Ning Chen, how many laps have you run over there?"
"It's almost 10 laps, how about you?"
"Not bad, I just finished 10 laps."
Although the two of them were not sure how far the other had run, neither of them had any doubts about the other.
At this time, Ning Chen felt that his physical strength was almost at its limit, but he gritted his teeth and persisted in running the last two and a half laps.
"Huh~ I'm finally done."
After running 5,000 meters, Ning Chen's whole body was soaked with sweat.
But the feeling of sweating heartily after exercise is really very comfortable, and even some of the depression accumulated in scientific research work is completely released.
Ning Chen looked at the time and found that it took him 25 minutes to run 5,000 meters this time.
Compared to when I was at my peak at Shuimu University, this speed is still slower.
"Ning Chen, can't you do this? I ran a little slower on purpose. It seems that you really haven't exercised these days." Ning Chen knew that Song Xiyun's words were true. If Song Xiyun ran with all his strength, he would at least be able to The time is shortened by another minute.
“Hey, my speed is pretty good, very close to the level of a national third-level athlete.”
“Is this just a national third-level athlete? You still Not even close.”
“It’s a female athlete, haha,” Ning Chen said with a smile.
In fact, Ning Chen feels that if she can reach the standard of a women's national third-level athlete, she will be very good.
After the two ran 5,000 meters, neither of them left the playground immediately. Instead, they walked around the playground for a while and chatted on the phone.
Whether it was mathematics, life, or various other topics, Ning Chen felt that he and Song Xiyun could chat very well. Perhaps this was a sign that the two had similar views.
"Ning Chen, is your phone bill still enough?"
Song Xiyun noticed that the call between the two lasted more than half an hour, and it was from outside the province. call.
During this period, phone calls were still very expensive, and the price of phone calls was divided into within the city, within the province, outside the city, outside the province, etc., and the price was not unified.
“Don’t worry, I just signed up for a nationwide calling package with 3,000 minutes per month. It’s no problem to make 100 minutes of calls every day.”
“Oh my god, you are too much. It's an exaggeration. 100 minutes a day is enough to run a half marathon."
The two of them walked and talked on the phone. Ning Chen didn't hang up the phone until Song Xiyun returned to the dormitory.
After returning home, Ning Chen took a shower, changed his clothes, and then continued to the study to do research.
Whether it was the effect of exercise or chatting with Song Xiyun, Ning Chen felt that his condition was better now than before running.
Ning Chen felt that perhaps these two reasons were both, and it seemed that this activity should continue.
......
Time passed day by day, and Ning Chen maintained such a regular life every day, enjoying the fun brought to him by research and exercise.
Except for the occasional bad weather, Ning Chen and Song Xiyun come to the playground every night and run on time.
Even if she was not feeling well for a few days, Song Xiyun would come to the playground and take a walk. In this way, she could accompany Ning Chen on her night run.
On this day, Ning Chen received good news during the experiment.
After continuous improvement, Ning Chen finally succeeded in synthesizing an ideal substance, and this substance is exactly the kind whose theoretical superconducting temperature reaches 55K according to Ning Chen’s previous calculations. substance.
Once this superconducting critical temperature is confirmed, Ning Chen will set a record for the superconducting critical temperature of iron-based superconductors.
“Teacher Xu, I’m going to the measurement center.”
"Ning Chen, have you finally successfully synthesized it?" Xu Zhou asked.
"Yes, Teacher Xu. This time I used an ultra-high pressure synthesis method. Through X-ray diffraction and scanning electron microscope measurement results, I confirmed that this material is indeed the material I had previously dreamed of."
"Well, then go and measure it quickly. I'll wait for your good news."
With the prepared samples, Ning Chen came to the measurement center, specializing in superconducting temperature measurements. 's laboratory.
Ning Chen was already very familiar with this experiment. He quickly adjusted the experimental environment and started the cooling process.
This time, when the measurement environment temperature was reduced to about 70K, Ning Chen began to slow down the temperature reduction so that he could record the experimental phenomena more accurately.
Ning Chen stared at the resistance display on the screen seriously, looking forward to the sharp change in the resistance display.
But this time, until the test environment temperature had dropped to 60K, the situation Ning Chen expected still did not happen.
At this time, Ning Chen felt a little disappointed, because this meant that there might be some problems with his previous theory.
But this is also a very normal thing. Ning Chen immediately adjusted his emotions and continued the measurement work of the experiment.
No matter what the superconducting critical temperature of this material is, or whether this material is a superconductor, Ning Chen will accept these results calmly.
So what if it fails? At worst, we can go back and analyze the reasons and continue the research.
But when the test environment temperature dropped to 55K, Ning Chen suddenly saw that the resistance measurement data on the screen began to change dramatically.
(End of this chapter)