Instruction
Through experimental studies on condensed matter materials such as LaAlO3/SrTiO3 heterostructures, Amorphous Alloy Zr41.2Ti13.8Cu12.5Ni10Be22.5, and thermally transformed metal oxides such as Vanadium Dioxide, Yang Ding Tian collected a large amount of experimental data, which he then handed over to Shen Qi to construct a theoretical system.
Yang Ding Tian lived in the laboratory. Except for taking a hot shower in his dormitory, he took care of all his needs, including eating, drinking, relieving himself, and sleeping, at the Shen Qi Mathematical and Physical Research Center.
Shen Qi finally understood why Yang Ding Tian to keep a cat. This ascetic, experiment-obsessed maniac needed a comforting little animal to keep him company, otherwise he would be too lonely.
Based on laboratory data, Shen Qi began drafting a review article. Taking LaAlO3/SrTiO3 as an example, he agreed that the origin mechanism of the high-concentration, high-mobility quasi-two-dimensional electron gas q2DEG at heterojunctions is polarization catastrophe.
While Shen Qi did not propose the polarization catastrophe theory, he verified its theoretical support for q2DEG in his own way.
What are the practical applications after verification?
In his review article, Shen Qi wrote that new oxide materials may be used in the research and development and manufacturing of future electronic devices, and the traditional electronics industry may usher in new changes. Of course, the commercial application of q2DEG materials still needs further research, but this field has broad application prospects.
Regarding the study of another oxide, Vanadium Dioxide (VO2), Shen Qi, based on certain experimental data and Computer Science simulation data, combined with the classical theoretical system of the topological and geometric properties of defects, boldly proposed a new hypothesis, which he tentatively calls "the disorder-order phase transition rule of compounds with multiple crystal phase structures".
VO2 is a typical compound with multiple crystal phases. At around 341K (67.85 degrees Celsius), VO2 undergoes a reversible transition from a low-temperature insulating phase to a high-temperature metallic phase, accompanied by reversible abrupt changes in optical, electrical, and magnetic properties.
This unique property makes VO2 a promising candidate for applications in fields such as optoelectronic material switches, smart glass, storage media materials, and laser protection.
Metal-insulator reversible phase transitions in compounds like VO2 have been a hot topic of research for scientists, but the mechanism of these phase transitions remains inconclusive.
Shen Qi's research revealed that the macroscopic physical phenomena of compounds with multiple crystal phase structures are determined by their microscopic structural characteristics. In the early stage of phase transition, a large number of ordered core regions are formed. During the phase transition, the cores continue to grow and come into contact with each other, while the intertwining of antiphase domains is disordered.
Through rigorous topological analysis, Shen Qi speculated that the formation of a superlattice is the result of ordering. Ordering is beneficial for us to control the reversible phase transition between metal and insulation, which theoretically follows a One-dimensional Lattice Model.
Through painstaking Mathematical Physics calculations and optimization of the calculation method for lattice dynamics, Shen Qi presented the basic equations of this model:
∫+∞-∞dux/dx/x-ζdζ=(1-v)b/2asin4πux/b
"I'm exhausted, it's too brain-draining." Shen Qi spent several months brainstorming, recruited a doctoral student to help him with experiments day and night, and finally wrote a review article of more than fifty pages.
More than half of this article consists of various experimental data, charts, and pictures, a small portion is theoretical analysis and speculation, and the concluding content is the final basic equation.
Shen Qi invited Yang Ding Tian to the Director's Office so they could admire his newly published review article together.
Yang Ding Tian came in carrying a cat. After seeing Shen Qi's masterpiece, Yang Ding Tian was shocked. "Director Shen, you're amazing! With a mere 5 million yuan in funding, you managed to produce research results worth over 5 billion yuan."
The cat was shocked. "Meow!"
"Dingtian, you deserve credit for this too. What I want to say is that this is only a preliminary research result, and your experiments will continue. This disorder-order phase transition rule, after repeated verification by me, only applies to some oxides and complex oxides. Even if the object is an alloy with a similar structure, it does not apply." Shen Qi stroked the cat's chin and said, "This cat has gotten fatter again. It seems our center is treating it well."
"So Director Shen will publish this review article?" Yang Ding Tian asked.
Shen Qi's translation review article, in PDF format, can be submitted to the Physical Review Letters submission page by clicking "Submit."
"My name is on the author list?" Yang Ding Tian's body trembled, his excitement was palpable. Being an author of a PRL paper while still a student is something many doctoral students wouldn't even dare to dream of.
"I wrote the article, but you basically did the experiments, so your name must be on the author list. This 973 Program is a series, and this review article is part of that series. As the experiments progress, we will publish sequels and bonus chapters. Since you're new here, I'm the main writer for this series' opening article. I hope you can grow quickly, and you will be the main writer for the subsequent sequels and bonus chapters. I will be responsible for reviewing them." After submitting the review article, Shen Qi forwarded the PDF file to Yang Ding Tian's email address.
After finishing, Shen Qi handed some draft paper and manuscripts to Yang Ding Tian: "The PDF is a presentation of the results, and these manuscripts represent the thought process. Take them back and study them. You can ask me if you don't understand anything."
Shen Qi has his own methods for supervising doctoral students. He doesn't treat doctoral students as laborers or lab dogs; imparting experience and knowledge is the most important thing.
Yang Ding Tian received the manuscript as if it were a treasure, and he also offered a suggestion. "Our previous experiments mainly provided data support for theoretical construction. Now that we have a preliminary theory, should our next experiments focus on applied research? For example, based on Director Shen's disorder-order phase transition rule, we can obtain commercial application data for the reversible phase transition of Vanadium Dioxide through experiments. It can be applied to many industries such as construction, electronics, automobiles, high-tech industries, and even the military. This is a patent; the wider the application and the higher the value, the more valuable it becomes."
"I understand the logic, but do you really think we can complete commercial R&D with just 5 million yuan, a few pieces of basic equipment, and two guns? Of course, in the initial stage, we can find some financially strong partners through industry-academia-research cooperation. Later, as our center grows, we can go it alone. But no matter how we go it alone, we won't directly face the market. Market competition is the responsibility of enterprises; universities and research institutions are responsible for technical support. Remember, we are researchers, not businessmen." Shen Qi had his plans; he was training scientists, not business elites.
Yang Ding Tian returned to the laboratory to continue his experiments and digest the theoretical knowledge taught by Shen Qi.
Shen Qi deduced the disorder-order phase transition rules and the basic Mathematical Physics equations of the One-dimensional Lattice Model, which consumed a lot of his inner strength. He needs to relax before throwing himself into the next stage of research.