Chapter 1177 Majorana Fermions and Decoherence of Quantum Entanglement

What would happen if the electrical energy was not attenuated during transmission?

What if a computer had exponential speed and perfect precision?

Regarding this question, Professor Duncan Haldane once gave a standard answer. And in the autumn of 2016, this physicist and two other colleagues won this year's Nobel Prize in Physics for their "discovery of topological phase transitions and topological phases of matter"!

Simply put, through rigorous experiments, they found that even the smallest scale of microscopic substances can exhibit macroscopic properties and have topological phases.

This sounds a bit difficult to understand. If you want to understand it, you have to understand the concept of topology.

We all know that the way mathematicians look at problems is often different from that of ordinary people. They are often used to seeing the essence through phenomena. Topology is such a discipline, which studies the properties of geometric figures or spaces that remain unchanged after continuously changing their shapes.

A classic example is that to a topologist, a donut and a coffee mug look the same because they both have a hole.

Because there is only one hole, you can transform a donut into a coffee cup and vice versa through a smooth deformation process... Even though this may seem incomprehensible or even inexplicable to the average person, it is actually because This mathematical method has already discovered many interesting things by scholars in other fields.

Especially in the field of physics and materials, many amazing discoveries in the 1980s were derived from the method of topology, which provided a theoretical basis.

It’s just that although people are used to applying topology to solve problems in the macroscopic world, they are at a loss as to whether topology can be used to deal with subatomic particles such as electrons and photons.

Because they are all affected by the strange laws of quantum physics, resulting in their size, position and even shape are in a state of uncertainty.

However, the 2016 Nobel Prize in Physics gave an affirmative answer to this proposition.

Even the subatoms in these microcosms conform to topological properties!

This theory obviously has no impact on everyday life, but it does open the door to a whole new world for the field of electrical engineering!

In the wonderful quantum world, these properties exhibit amazing stability and some remarkable properties in a special phase of matter. One of the most typical examples is the topological insulator.

In particular, this characteristic found in graphene materials directly led to the birth of SG-1 superconducting materials and carbon-based chips.

At the same time, this property also promotes the research of quantum computing.

According to the principle of quantum computer, it mainly stores information in something called a quantum bit (qubit) through the property that subatomic particles can be in different states at the same time. It is precisely because of this characteristic that quantum computers can solve problems at an exponential speed compared to traditional computers.

The problem, however, is that the subatomic particles that store data are so fragile that, unlike stable atoms, even a slight perturbation can change its state.

It is the so-called "decoherence" in quantum mechanics-any environmental influence may cause the collapse of the entangled state of the qubit!

To solve the problem, either noise reduction, anti-interference, or both, no matter which technical route is adopted, the subatomic particles must be stabilized.

And this is also one of the core problems in the development of quantum computers.

At the same time, it is also the subject that Lu Zhou has been researching these days...

Jinling Institute for Advanced Study, the laboratory on the third basement floor.

The empty room that was originally used as a spare sample room is now being filled with a lot of newly purchased equipment.

These include multi-functional physical property measurement systems, step meters, vibrating sample magnetometers, high and low temperature magnetoresistance testers, and in-situ freeze dryers, etc. Although the lineup is not luxurious, it can also be said that the sparrow is small Everything is complete.

In addition, in addition to these essential equipment for the study of carbon materials, there is also a light-curing 3D printer with a maximum precision of 8 microns, which is mainly used to print the plastic molds needed for experiments.

Carefully put a thin film the size of a thumb into the magnetron sputtering atomic layer deposition equipment, Lu Zhou carefully compared the data on the experimental form, and set new experimental parameters on the computer.

After finishing all the work, he finally breathed a sigh of relief, and hit the Enter button on the keyboard.

The green signal light is on, and the equipment in the laboratory starts to operate.

Holding the coffee, he returned to the office chair next to him and sat down. Lu Zhou glanced at his watch, thinking of something to pass the boring time for a while, when Xiao Ai controlled the drone and swayed over from the side.

Xiao Ai: 【Master, master! Just a moment ago! An amazing thing happened! φ(≧ω≦*)]

Focusing on the air half a meter in front of the small TV, Lu Zhou raised his eyelids and said in surprise.

"You upgraded?"

Xiao Ai: [Huh? Do you know all about it? ! Σ(°△°|||)︴】

Lu Zhou: "..."

Is this guy upgraded or downgraded...

Sighing in his heart, Lu Zhou ignored it, closed his eyes and entered the system space.

Branch technology is a branch of system tasks, and the experience accumulation of artificial intelligence and informatics experience are synchronized. The moment Xiao Ai's level was raised to LV4, his Informatics level was also raised from LV4 to LV5.

At the moment of upgrading, even if you don’t enter the system space, you can still see the dialog prompt...

【…】

[G. Informatics: LV5 (0/300,000)]

After confirming the property panel after the change, Lu Zhou touched his chin thoughtfully.

Sure enough, as he speculated, by observing various behaviors of players in the virtual reality world, the accumulation of the progress bar can be accelerated. In other words, in fact, the experience required by the branch of artificial intelligence is actually a sociological experience?

However, Lu Zhou didn't pay much attention to Xiao Ai now. After entering the system space, he just glanced at his own attribute panel and the progress bar of the branch technology, and then turned his consciousness back to the real world.

Opening his eyes, he saw that the small TV staring at the quadrotor had been dangling in front of him for a long time.

Xiao Ai: [Master, master, don't you want to praise Xiao Ai? (*/ω＼*)】

Lu Zhou: "Well, well done."

Xiao Ai: 【So perfunctory! QAQ]

"...It seems that the time is almost here."

Pretending not to see the dialog box on the small TV, Lu Zhou looked down at the time on the watch and muttered to himself.

As if to confirm his words, the signal light on the instrument not far away jumped from green to red.

Seeing this, Lu Zhou immediately ordered.

"Xiaoai, turn on the in-situ freeze dryer."

Xiao Ai: 【Received! (○`3′○)]

Although extremely reluctant, Xiao Ai complied obediently.

It's just that I don't know if it's his illusion. I always feel that this little guy's reaction seems to be getting more and more emotional...or in other words, more and more human-like?

Lu Zhou can't say whether this is a good thing or not.

After all, the way artificial intelligence processes information is completely different from that of the human brain. One is based on logic to determine emotions, while the other is based on emotions governing logic.

Maybe its existence will give birth to a brand new species?

Of course, it's too early to tell.

As its "guardian", Lu Zhou can only fulfill his responsibilities and take a step forward.

At least as far as the current performance is concerned, the little guy is quite obedient and obedient. He plays the role of a little assistant no matter in life or in research, and he absolutely obeys his orders without compromise.

It seems that my worries are a little unnecessary?

With the help of Xiao Ai, Lu Zhou transferred the sample from the magnetron sputtering atomic layer deposition equipment to the in-situ freeze dryer, freeze-dried the carbon-based chip sample, and then used a metallographic microscope to examine the thin film. The shaped chip was carefully observed, and the experimental data was recorded in the notebook on the side.

Now he has more than 30,000 points. According to the price offered by the system, he needs 120,000 points to exchange for a full set of quantum computer technology.

However, in fact, this valuation actually contains a lot of moisture.

If the problem is split, based on the problems that have been solved by the academic community, and the unsolved problems are raised, the points consumed can be reduced by 80% or even more than 80%!

So far, he has spent 20,000 points to overcome several key bottlenecks in the research, and the rest is his own understanding of carbon materials, Mott insulators, and Majorana fermions , by consulting some predecessors' research results and completing some promotional work on this basis.

For example, a topological insulator carbon material containing Majorana fermions, and a single-atom-wide superconductor layer superimposed on it without affecting the stability of Majorana fermions.

In this special topological phase material, subatoms can be protected.

In other words, the qubits formed under this topological phase will not change due to some small or local disturbances. It is far more stable than ordinary qubits, allowing our quantum computing to deal with the answers we want in a more precise and efficient way.

These tasks saved Lu Zhou at least more than 100,000 points.

It is also these jobs that give him the opportunity to use his points wisely.

This can be regarded as a manifestation of the saying "knowledge is power".

Carefully completing the last step of all the experimental work, Lu Zhou placed a layer of translucent graphene sheet as thin as a cicada's wing on the circuit mold prepared in advance.

As if looking at a perfect work of art, a sincere smile appeared on his face.

"All performance tests met expectations."

"The presentation is also impeccable, it's perfect!"

"... Sure enough, Majorana fermions are the perfect choice for making quantum computers!"

All that remains is to verify whether the hard work these days and the 20,000 points he spent are worth it.

After pressing the power button, Lu Zhou's heart almost reached his throat.

Almost instantly.

At the same time he pressed the button, the pre-set program completed running on the film. The signal processed and output by the logic circuit is transmitted to the display screen, and a line of clear characters is quickly displayed on the display screen——

【Hello World】

Seeing the characters jumping on the screen, Lu Zhou was overjoyed, his fists were tightly clenched, and he almost jumped up excitedly.

"Successful!"

Subconsciously shouted out the excitement in his heart, but Lu Zhou was taken aback by his behavior, and hurriedly checked the operation status of the equipment.

When he saw that the stable operation of this "thin-film" chip did not cause the "collapse of the qubit entanglement state" because of his cheers exceeding 80 decibels, Lu Zhou finally showed his heartfelt relief. smile.

It seems that this time...

It's really done!