The Science Fiction World of Xueba

Liu Tingbo acted very quickly. Early the next morning, he called and said that he helped Pang Xuelin to contact a big boss from the School of Materials Science and Engineering.

"Xiao Pang, I will introduce to you Academician Xu Xingguo, Director of our State Key Laboratory of Silicon Materials at Jiangda University and Director of the Institute of Semiconductor Materials. Academician Xu has been engaged in the research of semiconductor silicon materials for a long time. Materials, solar photovoltaic silicon materials, silicon-based optoelectronic materials and nano-silicon semiconductor materials, etc. He heard that you are interested in materials science, so let me take you to have a look. As long as you complete the professional courses at the undergraduate level, you can directly apply for him graduate students."

Listening to the voice from the other end of the phone, Pang Xuelin couldn't laugh or cry. Academician Xu is an expert in the field of silicon materials. If he really applied for his graduate degree, he would use carbon nanotubes to create carbon-based CMOS in the future, which would ruin his mentor. rice bowl!

Although he thought so in his heart, Pang Xuelin still agreed.

He is mainly good at the preparation of high-purity carbon nanotubes and two-dimensional graphene materials. If he can really persuade this boss to change his career, he might not be able to develop real carbon-based chips in the future.

"Okay, Dean Liu, have you made an appointment with Academician Xu, and when should I find him?"

"This afternoon, he happens to be free in the afternoon, we just go to the laboratory to find him!"

"Okay, then it's settled!"

...

At two o'clock in the afternoon, under the leadership of Liu Tingbo, Pang Xuelin met Academician Xu Xingguo at the State Key Laboratory of Silicon Materials in Jiangda Yuquan Campus.

Academician Xu is in his fifties, with a square face, thick eyebrows and big eyes. It can be seen that he should be a handsome guy when he was young. Even at this age, his figure is not out of shape in the slightest, and he is full of energy.

"Professor Pang, I have admired your name for a long time, and I have wanted to meet you for a long time, but I spent most of my time on the Yuquan campus, so I have not seen you. Today I finally met the real person!"

Xu Xingguo got up and smiled.

Although Pang Xuelin is young, his academic status is even higher than that of Xu Xinguo, who is an academician of the Chinese Academy of Sciences.

After all, in China, there are hundreds of academicians, but Pang Xuelin is the only figure at the level of the Philippine Award boss.

Therefore, Xu Xingguo did not neglect Pang Xuelin even if the other party wanted something from him.

"Professor Xu, hello!" Pang Xuelin smiled and shook hands with Xu Xingguo, "Dean Liu should have told you, I want to learn more about materials science, I don't know if you can do it here. convenient."

Xu Xingguo smiled and said: "It's convenient, I have no problem here, but if you want to be admitted to my graduate school, you must at least have the professional knowledge level of an undergraduate. I heard from Lao Liu that you have completed the self-study of the undergraduate course of materials science? "

Pang Xuelin nodded and smiled, "Yes!"

Pang Xuelin is speaking at a low level. In fact, he did not relax his studies during those years of wandering around the earth world, especially the basic knowledge of materials science and chemistry. From the perspective of the level of the graphene field, there is probably no one who surpasses him in this world.

Xu Xingguo smiled and said: "Well, I have a set of papers here. If you can achieve more than 80 points, then I will directly ask the School of Materials to organize a special professional test for you. If you can still pass, then you Write another graduation thesis, and the school will directly award you a bachelor's degree in engineering. Come directly to me to study as a graduate student next year, what do you think?"

Pang Xuelin said: "No problem!"

"Okay, then let's stop talking nonsense, you do this test paper first!"

Obviously, Xu Xingguo had already made preparations before, and handed a paper that smelled like ink to Pang Xuelin.

Pang Xuelin took the paper, found a place in the office, and started to answer with a pen.

Xu Xingguo and Liu Tingbo on the side did not speak,

Watching Pang Xuelin answer the question with great interest.

Although this paper was made by Xu Xingguo temporarily, it is more than a dozen questions long, but the questions involve all aspects of the field of materials science, and the difficulty is comparable to that of the postgraduate entrance examination questions for materials majors. It can be regarded as a comprehensive assessment of Pang Xuelin's professional knowledge.

For example, the first question is about the field of material physics.

【Explain the band structure characteristics of conductors, semiconductors and insulators. 】

Pang Xuelin glanced at it and wrote down the answer directly in the blank space.

For this basic question type, for Pang Xuelin, the answer has already been imprinted in his mind, and he hardly needs to think about it.

[Conductors contain unfilled bands. Under the action of an external field, the distribution of electrons on the unfilled bands shifts, thereby changing the original central stacking state, and the moving currents formed by electrons occupying different states cannot be completely offset. The current formed by the offset part is the macroscopic current. Insulators do not contain unfilled bands, and the electrons in the full state will not be affected by the external field to produce a distribution that deviates from the equilibrium state, while some insulators that contain empty bands...]

The second question, let Pang Xuelin explain the quantum size effect.

[Quantum size effect: When the particle size drops to a certain value, the electronic energy level near the metal Fermi level changes from quasi-continuous to discrete energy levels, and there are discontinuous highest occupied molecular orbitals and lowest unoccupied molecular orbitals in semiconductor particles Molecular orbitals, energy gaps widen, which in turn lead to optoelectronic and superconducting properties that are different from macroscopic objects, such as: the transition from conductor to insulator, the blue shift of spectral absorption, and the magnetic moment is related to the odd and even number of electrons...]

The third question is that in the preparation of one-dimensional nanomaterials, a vapor-liquid-solid growth mechanism is used. Let Pang Xuelin briefly describe the basic principles of this growth mechanism.

Pang Xuelin also won easily.

The next fourth question...

Question five...

...

It took less than half an hour for Pang Xuelin to complete all the answers to the test paper issued by Xu Xingguo.

"Professor Xu, I have answered all these questions, please take a look!"

Xu Xingguo took the scroll and went through it from top to bottom, feeling a little surprised.

Although these test questions are not difficult, they involve a lot of knowledge points and a wide range of topics, from material chemistry, material physics, material mechanics to new functional inorganic non-metallic materials, nanomaterials, artificial band gap materials, etc. Not only did Pang Xuelin answer these questions thoroughly within half an hour, but there were no mistakes or omissions in the middle, which is very rare.

Even some of his graduate students may not be able to do this.

This shows that Pang Xuelin has very solid professional basic knowledge in the field of materials science.

Liu Tingbo on the side asked curiously, "Old Xu, how did Professor Pang do?"

Xu Xingguo said with a smile: "It's better than I imagined, Professor Pang, if I hadn't seen it with my own eyes, I really can't believe that you can get a perfect score on this test paper, even some graduate students under me may not be able to do it." arrive!"