16: Chapter 16 International Ridicule and Internal Pressure

The arrival of Topologist was like a cool, efficient breeze blowing into the slightly tense and busy work atmosphere of the Xuance Group.

He was only a few years older than Lin Shen, wore black-rimmed glasses, had a gentle temperament, and did not speak much, but every word he said was to the point.

After reporting for duty, the first thing he did was ask Lin Shen to open up all raw simulation data, parameter setting files, and relevant first-principles calculation results in the "Star Sea" library (if any) regarding the bismuth selenide-niobium nitride heterojunction to him.

Lin Shen did as he was told.

Topologist sat in front of his workstation for over ten hours at a time, during which he drank only a few energy drinks, his fingers flying across the keyboard while complex mathematical formulas and programming code scrolled on the screen like a waterfall.

He not only reproduced Lin Shen's simulation but also introduced more precise electron-electron interaction corrections, considered the momentum-dependent form of spin-Orbit coupling, and even attempted to incorporate the dielectric screening effect of the underlying substrate (sapphire) into the model.

Two days later, Topologist found Lin Shen and Shen Hong with an electronic document filled with derivations and conclusions.

"Engineer Lin, Engineer Shen." Topologist's tone was calm and waveless, but the eyes behind his lenses shone with sharp light, "The 'sweet spot' you found earlier is basically correct, but it might be narrower than expected, and it is very sensitive to the interface dipole layer and the substrate-induced Rashba effect.

I recalculated the band evolution under different lattice orientations and found that the (001) orientation has the largest window, but it requires precise control of the bismuth selenide stoichiometry of the initial growth layer; if the deviation exceeds 2%, the topological edge states will be drowned out by trivial states."

He pulled up a new, more detailed band diagram: "However, there is also good news.

Based on this model, I searched for other possible two-dimensional topological insulator/superconductor combinations.

Theoretically, bismuth sulfide (Bi₂Te₃) combined with the same niobium nitride, under certain strains, may also produce similar topological superconducting edge states, and the tolerance for interface disorder seems to be slightly higher.

The MBE growth technology for bismuth sulfide is more mature than that for bismuth selenide."

"Additionally," he paused, looking at Shen Hong, "Engineer Shen, I have an idea regarding experimental verification.

Besides traditional quantized conductance and STM zero-bias peaks, perhaps we can design a transport measurement scheme with more 'topological' features.

For example, on the edge where Majorana zero-energy modes are assumed to exist, we could introduce a local magnetic impurity or gate voltage to observe its 'fractionalization' effect on quantized conductance, or look for indirect evidence of non-Abelian statistics—for instance, by measuring the variation of interference patterns with the magnetic field.

Although these experiments are more difficult, if they can be observed, they will be more powerful evidence."

Shen Hong listened very carefully, nodding from time to time, and recorded quickly in his notebook.

"Researcher Lu's approach is very inspiring.

Magnetic impurity control and interference measurement are indeed powerful means to detect topological properties, but they require extremely precise micro-nano fabrication and a lower temperature measurement environment, which might be close to the limit of a dilution refrigerator.

However, it is worth studying in depth as an alternative plan."

Lin Shen looked at these two new capable members who had quickly entered their roles and generated high-quality collisions, feeling much relieved.

The team's two legs—theory and experiment—began to step forward in coordination.

However, the external pressure did not ease at all because of the team's internal progress; instead, it followed them like a shadow, pressing step by step.

First, a group of Western tech media, led by "Cutting-Edge Technology Review," began to publish comment articles one after another, pointing their fingers at the "rash" and "propaganda-driven" nature of the Dragon Kingdom's recent moves in the field of cutting-edge technology.

An article titled "The Noise After Quantum Supremacy: Examining the Dragon Kingdom's 'Jiuzhang Special Project' and Unrealistic Topological Fantasies" wrote with sharp words: "Just as the Federation has established a leadership position in quantum computing with solid engineering achievements, the Dragon Kingdom has hurriedly announced the launch of the so-called 'Jiuzhang Special Project,' intending to catch up in a short time.

This 'Great Leap Forward' style of scientific research investment based on political considerations, besides wasting precious resources and creating false hope, is unlikely to yield substantial results.

Particularly puzzling is that one of its subordinate groups has bet its treasure on 'Topological Quantum Computing,' which is still in the theoretical fantasy stage.

This looks more like academic speculation to attract attention rather than a rigorous path of scientific development."

The article cited comments from several "internationally renowned physicists who wished to remain anonymous," claiming that Topological Quantum Computing "will not see the possibility of practical application within the next twenty years," and questioned whether the Dragon Kingdom has enough basic scientific foundation and experimental facilities to support such frontier exploration, implying that this is merely a "PR stunt to divert attention and appease domestic sentiment."

Immediately following this, a technical standards organization under the Federal Department of Commerce released a draft for public comment on the "Quantum Computing Technology Security and Ethics Framework."

The draft implicitly included clauses to bring core quantum computing hardware, software, and even certain algorithms under export control, and specifically emphasized review restrictions on quantum technology cooperation and exchanges "that may be used for military or strategic competition purposes."

Although no names were mentioned, the target and timing were self-evident.

More direct pressure came from within the Jiuzhang Special Project.

At the second plenary progress coordination meeting held by the special project command, the atmosphere became noticeably subtle.

Each mainstream technology route team reported their recent progress.

Academician Liu's team on the superconducting route announced a breakthrough in new Josephson junction materials, increasing single-qubit coherence time by 15%; Chief Tan's team on the ion trap route demonstrated a higher-fidelity multi-ion entanglement scheme; the optical quantum route and semiconductor quantum dot route also had their own highlights.

When it was Lin Shen's turn to report on behalf of the Xuance Group, he could clearly feel the gazes from the audience becoming much more complex.

There was curiosity, scrutiny, but more of a vague... questioning and impatience.

He reported as clearly as possible on the theoretical exploration progress of Topological Quantum Computing, the theoretical predictions for the bismuth selenide/bismuth sulfide-niobium nitride system, and the initially conceived experimental verification scheme.

He emphasized that this is a disruptive exploration facing the long term, requiring time and patience.

However, before he finished speaking, a senior professor from the superconducting route raised a question: "Comrade Lin Shen, I understand the importance of exploratory research.

But the core goal of the Jiuzhang Special Project is to produce results that can compete with 'athena' in the short term.

The theory of Topological Quantum Computing is beautiful, but its implementation difficulty is well-known; it's a case of 'distant water not being able to quench immediate thirst.'

Will tilting too many precious special project resources and time towards such a highly uncertain direction affect our pace of concentrating strength on breaking through key bottlenecks in the mainstream routes?

Should we not be more focused on how to quickly improve the number and quality of qubits in the superconducting or ion trap routes?"

His words drew agreement from many people.

A leader from the ion trap team also tactfully expressed: "Chief Tan, we agree that exploration should be supported, but resource allocation needs to be efficient and prioritized.

Can the topological direction first be used as a theoretical reserve, and then increase investment after the mainstream routes achieve phased victories?"

The general chairing the meeting looked at Academician Qin.

Academician Qin's expression was calm as he looked at Lin Shen: "Lin Shen, what do you think?"

Lin Shen took a breath; he knew this moment would come sooner or later.

The pressure of internal competition is sometimes more realistic and urgent than external ridicule.

"Teachers, I fully understand everyone's concerns." Lin Shen stood up, his tone sincere and firm, "The positioning of the Xuance Group has never been to compete for resources for short-term results with the mainstream routes.

Our mission is to find a 'second curve' that might change the rules of the game."

He pulled up the charts he had prepared: "This is our preliminary analysis of the core bottleneck facing the mainstream technology routes—the relationship between quantum error correction overhead and the number and quality of physical qubits.

According to existing theory and experimental data, whether it is superconducting or ion traps, to scale up to thousands of logical qubits, the required number of physical qubits, the requirements for fidelity, as well as the system's complexity and energy consumption will all reach an astonishing magnitude.

The 512 logical qubits of 'athena' are already an engineering miracle, but on the path to further expansion, costs and technical obstacles will skyrocket."

He switched the chart to demonstrate the advantage of Topological Quantum Computing in being immune to noise in principle, as well as its potential to theoretically significantly reduce error correction overhead.

"We must, of course, fully support the breakthrough efforts of the mainstream routes; that is the cornerstone of our current catch-up phase.

But at the same time, we cannot put all our eggs in one basket.

The topological direction might be a rugged path that can fundamentally bypass the 'stumbling block.'

Investing resources to explore it now, even if we fail, can deepen our understanding of quantum matter and information, providing inspiration for other directions.

And once there is a breakthrough, the return will be strategic."

He looked at the several professors who asked questions: "As for resources, what our Xuance Group is applying for is mainly theoretical computing resources, some extreme condition experimental machine time, and cooperation in top-tier material growth.

Compared with the investment required for large-scale preparation, integration, and measurement and control systems of the mainstream routes, these resources account for a very small proportion.

We value more the synergy of top-tier intellectual resources and cross-disciplinary idea collision."

His answer had both a clear understanding of reality and persistence in long-term layout; it both respected the importance of the mainstream routes and clarified the irreplaceable value of the exploratory direction.

Academician Qin listened and nodded slightly: "Comrade Lin Shen makes sense.

The Jiuzhang Special Project must be based on the present and strive to catch up, but also look to the future and plan for the long term.

Walking on two legs, or even multiple legs, is the robust strategy.

The exploration of the Xuance Group has its unique significance.

Regarding resource allocation, the command will consider it comprehensively to ensure key areas are supported while taking exploration into account.

I hope that all teams will strengthen communication and inspire each other, rather than hinder each other."

Academician Qin's words settled the matter, temporarily suppressing the internal controversy.

But Lin Shen knew this was just the beginning.

If the Xuance Group could not produce some convincing, even if just phased, substantive progress (such as a beautiful theoretical prediction or a preliminary design for a key experiment) within a reasonable time, the pressure from within would only grow.

After the meeting, Lin Shen felt a wave of exhaustion.

Not only dealing with technical difficulties but also balancing internal relationships and resisting external public opinion—this multi-dimensional pressure was much more complex and draining than when he was purely doing research.

Returning to the base, he convened a short meeting with the core members of the Xuance Group to report the situation at the coordination meeting.

Topologist pushed up his glasses and said calmly: "Expected.

The scientific community also has its own 'rivers and lakes'.

Our response is to do more solid work."

Shen Hong was more pragmatic: "Engineer Lin, then we must hurry.

Has the cooperation coordination letter with Professor Wu Qingquan's team at the National Laboratory of Materials Science been approved by the command?

We need to start the first round of sample growth attempts as soon as possible; even if it fails, we can accumulate experience and shut the mouths of those who say we are 'all talk and no action'."

He Yun also said: "I have optimized the model for the stress control of the niobium nitride thin film and can provide more specific growth process recommendation parameter ranges.

Chen Fan is also learning the relevant thin film characterization technology to prepare for the connection."

Seeing that the team members were not only not intimidated by the pressure but were instead inspired with stronger fighting spirit and initiative, a warmth surged in Lin Shen's heart.

"Good!" He cheered up, "Researcher Lu, continue to deepen the theory, especially the search for the bismuth sulfide system and other potential candidate materials.

Engineer Shen, you immediately start drafting the collaborative experimental plan with Professor Wu Qingquan's team, as well as the detailed technical requirements and machine time application report for the required extreme condition measurements.

He Yun, organize your process simulation parameters and give them to Engineer Shen as soon as possible.

We will advance on two tracks, with theoretical pre-research and experimental preparation pushed forward simultaneously!"

After the meeting, Lin Shen stayed in the studio alone.

The simulated night outside the window was deep.

International ridicule, internal pressure, like invisible shackles and surging undercurrents.

But he knew that true breakthroughs are always born amidst questioning and pressure.

The door to the topological quantum world might have only opened a tiny, imperceptible crack.

But they must, and will, use the most rigorous theory, the most exquisite experiments, and the most steadfast will to pry it open until that disruptive light illuminates the eyes of all doubters.

Although the road is long, if you walk, you will reach it.