ushernet Page 1212
Page 1212
"correct..."
"Professor Fan, do you think the physical properties of the Weyl semimetal I speculated are consistent with its Weyl fermion state?" Xu Mang asked.
Fan Zhilong shook his head and said seriously: "Give me half an hour, I need to take a good look at the content, I just glanced at it just now."
"Ok!"
"By the way, let me have breakfast." Xu Mang smiled and took out a ball of fried rice, and then sat in the corner to start eating. His ball of rice was relatively simple, with only a fried dough stick in it, and sprinkled it Take it with a pinch of salt.
But the simpler the food, the more delicious it tasted. Xu Mang almost felt the absolute balance between the glutinous rice and fried dough sticks.
at this time,
Professor Fan Zhilong began to read this manuscript, and the previous ones belonged to normal things, a solution derived from the Dirac equation. According to the interpretation of quantum theory, Weyl fermions are not a kind of elementary particles.
To be precise, Weyl fermions exist as quasiparticle excitations in condensate physics.
Then,
Professor Fan saw the miraculous transformation. From the existence of Weyl fermion states, he deduced the possible physical phenomena of Weyl semimetals. According to the three characteristics given by Xu Mang, Weyl cones, Fermi arcs and The chirality is abnormal, and Fan Zhilong vaguely associates it with a material.
He had encountered this kind of material before, but because it was too strange and the research was too difficult, it was directly abandoned.
"Xu Mang?"
"The physical phenomenon you predicted, I know that there is a material that is quite consistent." Fan Zhilong said seriously: "In the past... when I was studying the Dirac electronic state of topological semimetals, according to Dirac semimetal materials Theory, I have an idea."
Xu Mang froze for a moment, then looked at him in surprise.
"At that time, I was thinking...if a topological semimetal breaks into chiral Weyl cones by releasing the spin degeneracy on its Dirac cone, what kind of metal would it be?" Fan Zhilong said : "I didn't know what material it was at the time, but after reading your speculation about the Weyl semimetal, I found out...it might be a Weyl semimetal!"
What the hell!
Seems...seems to be the case!
By analyzing the hint given by Fan Zhilong, Xu Mang found that as long as the topological semimetal was changed, the so-called Weyl semimetal could appear.
"I rely on!"
"Professor Fan...you are amazing!" Xu Mang said with a smile, "What kind of material are you talking about?"
"do not know."
"I'm talking about changing the structure according to the topological semimetal, but what kind of material is after the change... I don't know." Fan Zhilong said helplessly: "This kind of breaking the inversion symmetry of time or space to realize Weyl semimetal, There is no small difficulty."
indeed,
The difficulty is not small!
According to Xu Mang's rough guess at the scene, Fan Zhilong's bold guess is to break the time-reversal symmetry by introducing magnetic atoms, or to realize the Weyl electronic state by continuously doping to adjust the composition and band structure.
but...
The magnetic domains brought by the magnetic atoms in the system and the destruction of the translational symmetry by the atoms will hinder the intrinsic properties of Weyl fermions.
How to achieve the Weyl electronic state by breaking the space inversion symmetry without requiring detailed and complicated regulation such as doping is the most critical factor at present.
"..."
"..."
The two stared at each other with big eyes and small eyes. The current situation is really embarrassing.
This problem seems to be unsolvable!
"Xu Mang..."
"The help I can provide can only go up to here, and the rest is up to you." Fan Zhilong said: "The Weyl semimetal material system is a research that has been very popular in condensed matter physics at present, and many people participated in it. in."
Xu Mang nodded, the Weyl fermion state is most likely to appear in condensed matter.
pity...
How difficult it is.
leave the lab,
Xu Mang came to the computer building slowly, and used the material science database to conduct a series of deletions based on three inferred materials, but the answer he got was no, which was another serious blow to Xu Mang.
How to do?
back to the apartment,
Xu Mang systematically explored this problem, and finally felt that he still needed to go through theoretical calculations. From the theoretical calculations, he could find materials that meet the properties. Whether it can be realized... Let's talk about it later.
...
"Elder Hua!"
"Do you know what Xu Mang is doing recently?" Fan Zhilong found Mr. Hua and said seriously, "He switched from your particle physics to condensed matter physics."
"what?"
"He... he doesn't study axes anymore?" Hua Yanfeng asked with a confused face, "What's going on? Does Xu Mang think that axes can't be discovered?"
Fan Zhilong shook his head and said seriously: "That's not the case... On the contrary, this is the only way to find the axis."
Hua Yanfeng hurriedly asked: "What's the matter?"
"Xu Mang thinks that Weyl fermions may be related to axions, but if we want to prove Weyl fermions, we need to find Weyl semimetals. I read his manuscript this morning and found that he has studied Weyl semimetals in great detail. of."
Although Hua Yanfeng is a professor of particle physics, he also has a little understanding of other aspects, such as this so-called Weyl semimetal.
It's... no simpler than an axion!
Although there are equations and relative solutions, it is still difficult to implement.
"This..."
"Unexpectedly, the research on axions will involve so many things." Hua Yanfeng said helplessly: "I guess he is busy during this time."
"Ha ha..."
"It's not just as simple as being busy."
"I reckon Xu Mang is in a state of desperation right now." Fan Zhilong said with a wry smile, "First we need to find Weyl semimetals, second we need to prove the existence of Weyl fermions, and finally we need to explore axions based on Weyl fermions."
"..."