22: Chapter 22: The Key to Unlocking the "Artificial Sun"

The new underground studio was less a room and more an island of information and a crucible of thought. The walls were lined with sound-absorbing material, the ceiling was embedded with soft, flicker-free light sources, and the only "window" was a massive screen capable of toggling between displaying various data visualization charts or simulated natural landscapes. The air circulation system emitted a nearly inaudible hum, maintaining a constant temperature and humidity.

Lin Shen had already spent seventy-two hours here.

In these seventy-two hours, his sleep had been compressed to his physiological limit, and his food was high-energy liquid nutrition prepared by a nutritionist, delivered through specific pipes. His entire mind and body were immersed in two distinct yet vaguely connected "universes."

Half of his consciousness was connected to the daily work of the Xuance Group and the Chasing Light photon group. Through encrypted video and data streams from the firefly channel, he listened to Topologist's report on the latest optimizations of the Topological Quantum Computing model, reviewed the preliminary electrical transport test plan submitted by Shen Hong for the first batch of bismuth sulfide-niobium nitride heterojunction samples, provided guidance for the light source efficiency bottleneck He Yun encountered in photonic integration, and finally approved Chen Fan's application to go to the National Laboratory of Materials Science to assist Professor Wu Qingquan's team with in-depth sample characterization. Although these tasks were heavy, the path was relatively clear, and the team was maturing daily, giving him a sense of steady progress.

The other half of his consciousness was like an exploration ship sailing into an unknown sea of stars, plunging headlong into the vast ocean of fusion energy data in the "Star Sea" knowledge base. Controlled nuclear fusion, the pearl on the holy grail of human energy, possessed a dazzling radiance that masked a daunting complexity and an abyss where countless pioneers had met their downfall.

He reorganized the two mainstream paths he had been familiar with before his coma: magnetic confinement fusion (primarily tokamaks) and inertial confinement fusion (laser or particle beam driven). The massive scale and long cycle of ITER (International Thermonuclear Experimental Reactor), the breakthroughs achieved by national major scientific facilities like EAST and HL-2M (such as plasma confinement at hundreds of millions of degrees for over a hundred seconds), the huge gaps that still existed (such as steady-state operation and the fusion gain Q value being far from the 10 required for practical application), the ignition success of laser fusion (NIF) along with its extremely low energy conversion efficiency, and the bottleneck of difficulty in repeatable rapid ignition...

Every path shone with the light of wisdom, yet was also entangled with seemingly unsolvable engineering and physical deadlocks. The stable confinement of high-temperature plasma (over a hundred million degrees Celsius), the durability of first-wall materials under extreme neutron irradiation and thermal loads, the self-sustaining production and safe handling of tritium fuel, the efficient extraction and conversion of fusion energy... each sub-problem was enough to exhaust the lifelong efforts of a top-tier team.

On the technology tree, the heavy grey "lock" on the [Controlled Nuclear Fusion] node and the dense, intertwined web of prerequisite requirements around it were a true mapping of this complexity and difficulty.

Lin Shen did not attempt to attack this behemoth head-on. He focused his main energy on the sub-node [Compact Fusion Device Concept] that Director Zhao had specifically emphasized.

This direction aimed to explore fusion devices that were much smaller than ITER or traditional tokamaks (potentially one to two orders of magnitude smaller in volume), might adopt different confinement principles (such as spheromak, field-reversed configuration, magnetic mirror, etc.), and were easier to modularly build and deploy. Its goal was not to pursue immediate commercial power generation, but rather to potentially serve as special energy sources (such as for deep-sea or deep-space bases), neutron sources, or even "igniters" for future fusion-fission hybrid reactors.

In the "Star Sea" library, research materials on compact fusion were relatively scarce, and most remained at the stage of theoretical discussion and extremely small-scale proof-of-concept experiments. Domestically, several teams were conducting related explorations, but the investment and progress could not compare to the mainstream tokamak route. Internationally, some private companies (such as the Federation's TAE Technologies, Helion Energy, etc.) had also invested heavily in this field, claiming to have achieved certain "milestones," but they were still far from truly realizing net energy gain (Q > 1).

Lin Shen carefully studied these materials. He discovered that the core challenges of compact fusion, beyond the general difficulties of fusion reactions, were more concentrated in a few specific directions:

Novel Plasma Confinement and Heating: How to achieve plasma with sufficiently high density, high temperature, and sufficiently long confinement time within a smaller scale? Concepts like Spheromak or Field-Reversed Configuration (FRC) relied on self-organizing magnetic fields; the theory was elegant, but stability was extremely difficult to control; magnetic mirrors had terminal loss problems.

Compact Strong Magnetic Field Technology: Whether for confining plasma or potentially for direct energy conversion, extremely strong magnetic fields were required. Traditional low-temperature superconducting magnets were large and heavy, and their cooling systems were complex. The emergence of high-temperature superconducting (HTS) materials brought a glimmer of hope, but their performance under strong magnetic fields, mechanical strength, and how to wind them into complex magnets suitable for compact devices remained huge challenges.

Efficient Tritium Breeding and Fuel Cycle: Compact devices had limited space, and traditional solid breeder layer (such as Li ceramics) schemes might not be applicable. It was necessary to explore more efficient liquid metal or molten salt breeding concepts and integrate them with compact fuel extraction and purification systems.

Materials and Energy Handling: Small scale meant that the first wall and neutron shielding faced more severe power densities, requiring the search for new materials more resistant to extreme irradiation and thermal shock. Energy extraction from fusion products (high-energy neutrons, alpha particles) also required more compact and efficient schemes.

Each of these problems was spanned by a huge knowledge gap.

But Lin Shen also discovered some interesting "fringe" information. An internal report from the National Key Laboratory of Superconductivity mentioned that they had made a breakthrough in the critical current performance of a certain new type of high-temperature superconducting tape (based on the rare-earth barium copper oxide system, REBCO) in strong magnetic fields (> 20T), and had begun to explore the possibility of using it for compact nuclear magnetic resonance and future fusion magnets. Another theoretical study from a university discussed the use of ultra-strong femtosecond lasers interacting with special targets to generate extreme high-pressure and high-temperature conditions, which might provide new ideas for inertial confinement fusion, although it was currently just pure numerical simulation.

These sporadic highlights, which had not yet formed a mainstream, were like shells scattered on a beach, waiting for someone with intent to pick them up and string them together.

Lin Shen let his thinking diverge. He no longer thought solely from the framework of fusion engineering itself, but instead tried to invoke the new insights and ways of thinking he had acquired during this time in the fields of photonics, quantum, and material interfaces.

Photonics? High-power lasers were the core driving source for inertial confinement fusion; the efficiency, beam quality, and repetition frequency of the laser directly determined its energy prospects. Could the miniaturized, high-efficiency light source and light manipulation technologies he was researching in photonic integration provide even a little inspiration in principle for future, more efficient, and more compact laser-driven fusion? Even if it was just a theoretical association?

Quantum? Plasma was essentially a highly complex quantum many-body system. Could the ideas for handling complex interactions and finding robust states in Topological Quantum Computing, along with those profound mathematical tools (such as tensor networks and renormalization groups), provide a new perspective for understanding and simulating the "stumbling blocks" of turbulence and instability in plasma? Even if it only provided a different thinking framework?

Material Interfaces? The silicon-based interface engineering he had been deeply cultivating centered on manipulating the properties of material surfaces and interfaces at the atomic scale. Did some deep common logic exist between this and the interface science of the interaction between first-wall material surfaces and extreme plasma in fusion? Could the microscopic understanding of interface defects, impurity adsorption, and energy transfer be mutually referenced?

These ideas might seem whimsical to others, perhaps even absurd, given the huge span of disciplines. But Lin Shen felt that, under the faint, cross-domain "sense of resonance" from the technology tree, this kind of association that broke down barriers might be the key to discovering "non-traditional" breakthrough points.

He temporarily noted down these vague associations as "sparks of inspiration" waiting to be explored. Then, he focused his attention on one intersection point that currently seemed to have the most potential for engineering realization—high-temperature superconducting strong magnetic field technology.

Whether it was magnetic confinement fusion (which required a confining magnetic field) or some novel direct energy conversion schemes (such as magnetohydrodynamic power generation), strong magnetic fields were a core requirement. And the progress in high-temperature superconducting materials was the hope for realizing compact, efficient strong magnets.

On the technology tree, under the [Compact Fusion Device Concept] node, there was indeed a prerequisite requirement path that clearly pointed to [High-Performance High-Temperature Superconducting Magnet System].

Lin Shen decided to position the first "key" to "unlocking" fusion energy here. He wanted to deeply investigate the current performance limits of high-temperature superconducting materials under strong magnetic fields, the technical bottlenecks in magnet design, and how to perform integrated optimization design with other subsystems of the fusion device (such as cryogenic cooling, structural support, and plasma coupling).

Through the "firefly" channel, he submitted a preliminary work plan and resource request to Director Zhao and Academician Qin:

Request for Access: Comprehensive access to all R&D, preparation, and characterization data on high-temperature superconducting materials (especially materials suitable for strong magnetic field applications such as REBCO, Bi-2212, etc.) in the "Star Sea" library, as well as design cases and research reports on domestic and international compact fusion magnets.

Expert Consultation: Request to arrange small-scale, high-security academic exchanges with top domestic high-temperature superconducting material teams (such as the Key Laboratory of Superconductivity that submitted that internal report) and engineering experts engaged in compact fusion magnet design.

Computing Resources: Application for additional "tianhe-3" computing power quota to perform multi-physics field simulation of high-temperature superconducting magnets in extreme fusion environments (strong irradiation, high stress, thermal cycling) to evaluate their long-term operational reliability.

Cross-disciplinary Seminar: Suggest organizing a small-scale, cross-disciplinary "brainstorming" session, inviting a few top experts (must be kept strictly confidential) in the fields of fusion physics, superconducting materials, plasma simulation, and even quantum information and photon technology, to jointly discuss the possibilities of "non-traditional" fusion realization paths.

His request was quickly approved. Director Zhao's instructions: "Broad thinking, clear grasp. Request approved, full support. Hope to form a phased judgment as soon as possible."

New data flooded in like a tide, and new expert liaison channels were established. Lin Shen's workstation screen was gradually occupied by phase diagrams of high-temperature superconductors, flux pinning mechanisms, tape stress-strain curves, magnet quench protection circuit diagrams, and conceptual design sketches of various compact fusion devices.

Meanwhile, the storm in the international energy market intensified. News briefings showed that oil prices continued to rise after breaking through $150, and many countries announced they were entering a "state of energy emergency." The atmosphere of military confrontation in the Xingzhou Strait was becoming increasingly thick, and the risk of accidental gunfire continued to climb. The Federation and its allies were using the energy crisis to exert comprehensive pressure, demanding that the Dragon Nation make "substantial concessions" in multiple fields such as trade and technology.

The pressure was like a tightening noose.

But in this information fortress buried deep underground, Lin Shen entered a peculiar state of "flow." The clamor of the outside world seemed to be shielded layer by layer, and his entire focus was on how to find that potential, deep path leading to the "artificial sun" amidst the microscopic arrangement of atoms and the macroscopic giant energy system.

He seemed to see that on the technology tree, under the [Compact Fusion Device Concept] node, the path pointing to [High-Performance High-Temperature Superconducting Magnet System] began to heat up slightly, as if extremely subtle data streams were beginning to inject, calculate, and deduce.

There might be more than one key, but the process of searching for the first key itself was the beginning of illuminating the darkness and dispelling the confusion.

He stretched his neck, which was somewhat stiff from sitting for a long time, and cast his gaze toward the massive screen. It was displaying in real-time the preliminary calculation results of the performance evolution of the first high-temperature superconducting magnet, returned by "tianhe-3" under simulated fusion neutron irradiation conditions.

The curve had just begun to be plotted, and the future was uncertain.

But the steps of exploration had already been taken.