Chapter 366: Breakthrough Limit
“Actually, the Hubble Telescope is still pretty good, after all, its error is very small, and the lens itself is a very precise thing.
Even more outrageous is during the first Apollo Moon Landing, Buzz and Neil almost couldn’t get out, do you know why?”
Li Xiaoman asked: “Why?”
For this kind of secret anecdote, she really didn’t know.
“NASA designed the hatch to open inward, the space inside the cabin was already small, and the astronauts’ spacesuits were very bulky, filling up the entire cabin space, opening inward almost made the door unable to open.
If the door couldn’t be opened, they might not even be able to return.
Logically, this should have been tested on the first day, but in reality, no one discovered the problem until the actual moon landing, when Neil opened the door and realized something was wrong.
Reality doesn’t need logic.
If Xiaomi’s LOGO wasn’t discovered, maybe really no one would notice, everyone was careless, or maybe someone noticed but thought it was nothing, then everyone thought it was nothing, or thought that if it was a problem, the leader would point it out, the next step someone would point it out.
To the point that in the end, no one pointed out it was a problem.
Reality doesn’t need logic, but Americans, not to mention anything else, are too strong in discovering problems and solving them.
So quickly grabbing Lei Zong, forcing Lei Zong to delete the clarification announcement that had already been issued, that’s really impressive.”
General Aerospace also issued an announcement synchronously, claiming they found Xiaomi for investment, facing doubts from conservative congressmen, whether this violated the Wolf Amendment, after all, the VIPER Lunar Rover comes from NASA.
In the White House controlled by the Donkey Party, this is a negligible small problem, it can all be covered up.
After the astronauts returned to Earth, the old timers excitedly held a celebration ceremony for them at the White House, and awarded the corresponding Medal of Honor.
The old timer was really happy, after all, this is an unprecedented breakthrough, completing the moon landing during his term, the Artemis program started being mentioned from the Obama era and never succeeded, now he answered this question: when exactly can America land on the Moon.
Although this used China technology, if you look at American Media, you’ll find all media are silent about it, as if it never happened.
Everyone is talking about the success of diversity, compared to the moon landing in the 60s, this time not only female astronauts landed on the Moon, but black women, this is progress of the era, a symbol of significant progress in diversity and equality.
The two women, black woman and white woman, achieved double harvest of career and money, sponsorships from various brands came flooding in.
The white male astronaut waiting for them in the Command Module, just like the technology source, was drowned in public opinion, as if he wasn’t a member of the moon landing trio at all.
“Mr. Buzz, how did our country become like this?” Colonel John Smith was vacationing in Florida, staying at Buzz’s house.
Buzz really liked this new American astronaut who landed on the Moon, he had already fallen out with his own children and wife, he wished John Smith would come.
“I’m not jealous, I just feel it’s very strange, from newspapers to television stations to social media, everything is focused on, we sent women to the Moon, we sent black people to the Moon.” John Smith said gloomily.
Aldrin shook his head: “I don’t know either, I think our country is definitely sick, but whether this disease can be cured, I have no way to give you an answer.”
The Donkey Party thought they had a great victory, thought diversity had taken a big step forward, little did they know, in the sky of the narrative logic building constructed by the Donkey Party’s diversity discourse, two dark clouds had already appeared:
One called Big T, the other looking like Musk, actually Twitter.
These two dark clouds, in the soon-to-come presidential election, would turn into torrential rain, sweeping from America across the whole world, smashing the narrative logic built by the Donkey Party in the past to pieces.
“Nanping, after taking this step, it’s the comprehensive reconstruction of the world vision.”
On the blackboard is a calculus formula:
After Li Xiaoman left, the one who came to Lin Ran’s office was Song Nanping.
This matter is of great importance, Lin Ran didn’t even communicate with Pony Ma, but found Song Nanping.
He knew Song Nanping was from Yanjing, which also meant the other party was absolutely reliable.
“Professor, this is?” Song Nanping’s heart was pounding inside.
Comprehensive reconstruction of the world vision, if someone else said it, it would definitely be bragging.
But this is Lin Ran, the man who once did the impossible, he naturally believed the other was telling the truth.
The formula in front of him looked very complex at a glance.
“Nanping, do you know why the photoelectric conversion efficiency limit of solar cells is only 33.7%?” Lin Ran asked.
Song Nanping smiled bitterly: “Professor, how could I possibly know.”
“Because of the Shockley–Queisser Limit, this limit restricts the limit of single-junction solar cells.
The photovoltaic cells we are widely mass-producing now haven’t reached this limit, the photovoltaic cells commonly mass-produced on the market have photoelectric conversion efficiency around 20%.
How to approach this 33.7 limit, we can transform it into a quantum statistical optimization problem with boundary conditions, the constraints are single-junction and equilibrium state.
Then solving this mathematical problem, finding the optimal solution, we can naturally find the optimal structure, letting photovoltaic cells achieve the best effect.
Now raising the photoelectric conversion efficiency from 20% to 30%, Nanping, what do you think that means?”
Song Nanping murmured: “It means, the importance of photovoltaic power generation in China’s electricity sector can increase significantly, it means we can further promote clean energy.
It means the penetration rate of new energy vehicles can accelerate further.”
Lin Ran nodded, “Then what if we can break through this limit?
Exceed the 33% limit, destroy the boundary conditions?
If it can directly become 50%, and the cost won’t rise significantly compared to the past?”
“This means global electricity prices drop sharply, electricity price reshaping, photovoltaics can unfold in more scenarios, the scenario of photovoltaics replacing traditional fossil fuel power generation instantly established.
Energy security will shift from oil and gas producing areas to efficient solar modules and upstream materials, the importance of the Middle East will drop significantly, we will have new diplomatic chips.” Song Nanping understood what Lin Ran meant by reconstruction.
Controlled nuclear fusion is a technology that can reconstruct everything, no doubt, but if photovoltaics can break through, it’s also a technology that can reconstruct everything.
According to the International Energy Agency’s statistics, the cost of China’s photovoltaic power generation is 0.033 USD/KWH, coal’s cost is 0.068, natural gas cost is between 0.10 and 0.14.
So some people ask, photovoltaic power generation has the lowest cost, why not use all photovoltaics? Because photovoltaics depend on solar output, no output at night, power generation drops sharply on cloudy and rainy days.
If photovoltaics need all-weather supply, they need long-duration energy storage.
Energy storage cost is three times the fuel cost.
At the same time, photovoltaic power generation is concentrated in the west, while the electricity consumption center is on the southeast coast, ultra-high voltage transmission capacity is limited.
But if the cost of photovoltaics can drop another 2.5 times, the situation is different.
“Yes, I have solved the quantum many-body transport optimization problem under non-equilibrium state, this means we have found an engineering feasible solution mathematically.
In this brand new, precisely designed electron density of states, phonon spectrum, and light absorption cross-section, the energy conversion path of photons will no longer be limited by thermalization loss and single exciton.
To put it more bluntly, this design breaks through the Shockley–Queisser Limit, its efficiency can reach 50%, and it only needs process optimization, no need for any new materials.
The door to a new world is about to open.”
“Awesome.” After hearing this, Song Nanping had no other thoughts, it was indeed awesome.
“Professor, so you called me here to notify the Yanjing side, to do some financial operations, and also some resource tilt, adjustments in energy policy? Possibly establish a new large state-owned enterprise to unify the promotion of photovoltaic replacement?” Song Nanping continued.
Lin Ran waved his hand: “This is a bit early, what I mean by saying this is, I have solved this problem at the theoretical level, so I need the China side to help organize a group of sufficiently reliable professors to help me demonstrate it at the experimental level.
And to get through the large-scale engineering process flow.
Of course, the China side can prepare for the rainy day, do some capital operations.
Because this requires this group of scholars to do closed experiments, short as three months, long as half a year.
And what I need are young and promising scholars who can do experiments, preferably young scholars, academicians and such, they haven’t done hands-on experiments for decades, so forget it.
This aspect needs to rely on the official to help me coordinate and organize.”
Young and promising? Song Nanping who hasn’t been online less only heard two words: workhorses!
Wants workhorses who can do experiments, not old timers who only know how to command.
“Understood, I’ll go arrange it now.”
Lin Ran continued: “Also venues and such, all need the Yanjing side to organize, actually best in Shanghai, I don’t really want to go to Yanjing.”
Song Nanping nodded: “Okay.”
As for why not find people inside Apollo Technology to do experiments, because there’s not enough talent in this aspect.
Apollo Technology itself doesn’t do photovoltaic materials research and development.
China has the most in universities for this kind of thing, perovskite batteries various approaching the limit, in the past decade, perovskite is the richest mine for publishing papers, almost every university’s materials department has experts in perovskite.
Relying on this, young scholars applying for Qingqian, Guoji are not few.
If you want to do work in this area, relying on China official to organize is the most efficient.
Lin Ran doesn’t have the idea of doing all business himself, putting all money-making business in the Apollo Technology basket.
The project led by Lin Ran, the photovoltaic project that can still change the world vision, definitely the most coming are workhorses from Shanghai Jiaotong University, no, young scholars.
Shanghai Jiaotong University has a lot of people doing this kind of work.
Jiang Tailiang and Zhao Yibing were also called, of course not just them two, Jiaotong University sent about fifty people, out of total about two hundred, Jiaotong University accounts for more than a quarter.
Everyone’s direction is similar, they all know each other, just difference in closeness of relationship.
Jiang Tailiang and Zhao Yibing have a good relationship, they have co-authored many papers, one Tai Liang one Yi Bing, naturally easier to get close.
Because it was already end of year, Chinese New Year soon, first the institute urgently notified them to prepare clothes, to be prepared not to go home for New Year, there is a temporary urgent important task.
This made them very puzzled, logically, for materials, there shouldn’t be such task assignment.
They haven’t taken on classified projects either.
Then arranged in a place in Shanghai suburbs that looks unusual at a glance, everyone greeted each other and realized about two hundred people came.
The next day, in the large lecture hall, Lin Ran stood at the podium, everyone suddenly realized.
I wondered which immortal has the ability to gather us, Ran Shen, this is not surprising.
The youngest two academies academician, having this strength is expected, not to mention he is highly valued, reputed as China’s greatest hope for technology breakthrough.
Zhao Yibing said softly: “Professor Lin is not surprising, but does he call us for some major news to announce?
Or some major project to tackle.”
“Photovoltaic modules for the Moon Base, I guess, after all, for Moon supercomputer, one of the most important conditions isn’t energy?
On the Moon, in the shadowed region, no illumination, under illumination, definitely moon dust and solar wind, how to guarantee stability, quality and lifespan of photovoltaic modules is very important.”
But none of them guessed right.
Lin Ran stood up and said: “Everyone, this time calling you all, our time is tight, need everyone’s cooperation, start from some theoretical knowledge, I’ll slowly explain what I need you all to help with.
Everyone knows, what we see now are single-junction solar cells, some multi-junction solar cells, essentially stacking multiple single-junction cells with different band gaps, letting them each absorb photons in different energy ranges, thereby reducing thermalization loss and transmission loss.
From the physical mechanism, it hasn’t fundamentally changed the energy conversion principle of single-junction, just broke through the Shockley–Queisser Limit in a statistical average sense.
Each layer’s single-junction efficiency is still constrained by the Shockley–Queisser Limit.
I know, among you all, some have achieved similar results, published papers, actually you bypassed the hardest problem with physical structure.
The content I want to talk about today is, directly eliminate the Shockley–Queisser Limit inside single-junction, solve this problem through non-equilibrium quantum many-body transport optimization.”
Lin Ran started writing on the whiteboard behind him:
“The mathematical essence of the Shockley–Queisser Limit is a variational optimization problem constrained by spectral distribution, physical input is quantum absorption rules, the final mathematical result obtained is this limit, that is, the efficiency extremum.
But now we need to decouple this problem, destroy the limit, let the limit no longer exist.”
“Did you understand?” In the evening back to the dorm, Jiang Tailiang asked.
The dorm is two per room, free allocation, everyone has good relationship, Jiang Tailiang naturally with Zhao Yibing.
Lin Ran talked about three problems in total.
The first is in quantum many-body systems, modeling the photon absorption process as nonlinear probability optimization of many-body state transitions, solving the non-equilibrium quantum dynamical equation that parallels and maximizes multi-exciton yield in this strongly coupled electron-hole system.
The second is an optimization problem of time-dependent quantum Boltzmann equation, decoupling the rate equation of electron-phonon scattering, ultimately making scattering time longer than carrier collection time.
The third is spectrum reconstruction, frequency conversion optimization problem of nonlinear optical processes.
Finally entering the non-equilibrium quantum many-body transport optimization problem.
Combining the answers to the above problems, Lin Ran finally gave a precise value on materials, the structure designed according to the precise value can bypass the Shockley–Queisser Limit, achieve higher photoelectric conversion efficiency.
“Didn’t understand.” Zhao Yibing answered.
“No, you didn’t understand, why were you nodding frequently during class in the daytime? I thought you understood.” Jiang Tailiang’s suspended heart finally relaxed, I thought only I didn’t understand.
Zhao Yibing said: “Isn’t this contradictory, this is me expressing appreciation for Professor Lin’s achievement.
If I could understand, would I be an associate professor in materials science? I would have been a professor long ago!
If not for my weak theoretical foundation.”
Theoretical foundation, more bluntly, weak math foundation.
“I didn’t understand either, how to prove the professor is right?” Jiang Tailiang asked.
Zhao Yibing spread both hands: “Do experiments, isn’t calling us here for doing experiments?
I checked, those who can come are basically experiment experts.”
Jiang Tailiang nodded: “I guess so, but since that’s the case, why talk so much to us, just say the result directly.”
Zhao Yibing guessed: “Probably selection, selecting talents among us!”
Jiang Tailiang was a bit excited at first, following Lin Ran is more promising than at Jiaotong University.
Then immediately deflated, “I can’t even understand, looks like I’m not this talent.”
The next day, Lin Ran said:
“Believe everyone has some guess about what we are going to do.
After all, from principle breakthrough to mass-producible modules, that is, so-called industrial production, there is a long way to go.
I need everyone to help me complete a single-chip device with 50% photoelectric conversion efficiency in the laboratory, and find the method for engineering mass production.”
Many young scholars in the classroom started raising hands.
Lin Ran pointed to one, “What doubt do you have.”
“Professor Lin, laboratory single-chip device is not difficult, we should be able to make it in a few months.”
Everyone in the room nodded.
Laboratory can tune slowly, just matter of time length.
Single-chip device conversion rate over 50%, this achievement not to mention Science, this is absolutely Nobel Prize level.
Just Lin Ran giving the solution to break through Shockley–Queisser Limit at theoretical level is enough for Nobel Prize.
But mass-producible this proposition is too big, not even something that can be done in a year or two.
“For engineering path, like material manufacturability we need to find slowly, what materials to use, then lifetime under non-equilibrium state.
Mathematically we can assume non-equilibrium electron state lasts hundreds of picoseconds, but in actual materials maybe tens of femtoseconds and thermalizes.
On device structure design, need extremely fast carrier extraction mechanism= , collect it before electron loses energy, electrodes, interface defects, photon management all need to match.
Then industrialization also needs to face tests of cost, lifespan and environmental stability.”
Lin Ran nodded: “Of course, I know what you said, from mathematical solution to laboratory single-chip device is first step, from laboratory device to industrial mass production module is second step.
If I only want to do the first step, why do I need two hundred people? I could directly cooperate with Jiaotong University Materials College?
Publish a Science, I at most bring fifty people to co-author?
What you just mentioned, the second step, from laboratory device to industrial mass production, every link, I have found the mathematical optimal solution for everyone, I have already done the theoretical level demonstration, what everyone needs to do is give me feedback from the experimental end.”
Everyone started with half-believing half-doubting attitude, in the following time just as Lin Ran said, for big nodes, he had already done the theoretical optimal value solution.
The whole progress was like pressing the acceleration key.
“I finally know why General Manager Lin’s Apollo Technology could complete the moon landing in just over a year, this is a bit too terrifying.
Today in free time chatting with colleagues in our group, he said, General Manager Lin is like having cheats on.
Generally our tech world’s path to change industry is, like many years ago there is theoretical breakthrough, then later people slowly from theoretical breakthrough have some experimental breakthroughs, after these breakthroughs accumulate, industry finds some usable papers or achievements, then does industrialized mass production.
Such intermittent may take decades, countless researchers’ efforts.
Because achievements in the same period are thousands, no one knows what’s important, what was important then may not be in the future, what was obscure then may shine in industry in the future.
No one knows how this road should be walked.
Everyone digs treasures from predecessors’ old papers, then based on treasures, forges their own divine weapons.
Now General Manager Lin is equivalent to violently cracking from applied mathematics level, directly giving us the full map, telling you which things are useful, which direction to go, directly a straight road past.
This feeling is really too magical, with such cheats, no wonder Americans can’t compete with in aerospace field.” Zhao Yibing sighed.
In 1917 Einstein proposed stimulated emission theory, the core principle of world lasers, but at that time it was just abstract concepts in physics.
Until 1960, Theodore Maiman built the first working laser in laboratory, then considered no practical use.
In the 70s lasers started used in silicon chip etching and industrial cutting and welding, countless researchers participated in optimization, overcame stability problems.
From obscure paper to technology covering medical, communication, chip fields, took fully fifty years.
Including transistors, from field-effect transistor concept to semiconductors, also took over fifty years.
Now, the young scholars participating in this project, they are like having acceleration key pressed, theory directly usable, directly give you models derived from theory and optimal solutions.
You just need to be responsible for experiments.
This is an unprecedented experience.
As for being kept here unable to go home for New Year, highly confidential, isolated from the world, in front of the great cause to do, seems all tolerable.
They also know, if there are results in the end, national level definitely won’t treat them poorly.
Associate professor can remove the associate, up or out young teachers can not leave, full professor getting a collective science and technology progress first prize is not too much?
