What in the world is topological quantum matter? - Fan Zhang

譯者: Helen Chang 審譯者: S Sung

What if electricity could travel forever without being diminished?

如果電力能夠傳到無限遠處 而強度絲毫不減，會如何？

What if a computer could run exponentially faster with perfect accuracy?

如果電腦能以指數級的速度運算 完完全全準確，會如何？

What technology could those abilities build?

可以用什麼技術來達成呢？

We may be able to find out thanks to the work of the three scientists

我們或許能夠明白 這要感謝三位科學家

who won the Nobel Prize in Physics in 2016.

他們贏得了 2016 年的 諾貝爾物理獎

David Thouless,

大衛 · 杜列斯

Duncan Haldane,

鄧肯 · 哈爾丹

and Michael Kosterlitz won the award for discovering

和約翰 · 邁克爾 · 科斯特利茲

得獎的原因是發現了 即使在最小規模的微觀事物

that even microscopic matter at the smallest scale

can exhibit macroscopic properties and phases that are topological.

也會呈現出宏觀的拓撲性質與階段

But what does that mean?

但這是什麼意思？

First of all, topology is a branch of mathematics

首先，拓撲是數學的一分支

that focuses on fundamental properties of objects.

著重於物體的基本屬性

Topological properties don't change when an object is gradually stretched or bent.

當物體逐漸伸展或彎曲時 它的拓撲屬性不會改變

The object has to be torn or attached in new places.

靠撕裂它或黏上其他部分才會改變

A donut and a coffee cup look the same to a topologist

拓撲學家眼中的甜甜圈 和咖啡杯看起來一樣

because they both have one hole.

因為二者都有一個洞

You could reshape a donut into a coffee cup

你可以重塑甜甜圈成為咖啡杯

and it would still have just one.

它仍然只有一個洞

That topological property is stable.

拓撲性質穩定沒變

On the other hand, a pretzel has three holes.

另一方面，椒鹽捲餅有三個孔

There are no smooth incremental changes that will turn a donut into a pretzel.

沒有任何微調 能把甜甜圈變成椒鹽脆餅

You'd have to tear two new holes.

必須撕兩個新孔才行

For a long time, it wasn't clear whether topology was useful

有很長一段時間 不清楚是否能用拓撲

for describing the behaviors of subatomic particles.

來描述亞原子粒子的行為

That's because particles, like electrons and photons,

那是因為像電子和光子這些粒子

are subject to the strange laws of quantum physics,

被「量子物理」這奇怪法則所約束

which involve a great deal of uncertainty

涉及到很大的不確定性

that we don't see at the scale of coffee cups.

我們在咖啡杯的規模是看不到的

But the Nobel Laureates discovered that topological properties

但諾貝爾獎得主發現

拓撲性質確實存在於量子的層面

do exist at the quantum level.

And that discovery may revolutionize materials science,

而這一發現可能會 將革命性的進步帶至材料科學

electronic engineering,

電子工程

and computer science.

和計算機科學

That's because these properties lend surprising stability

那是因為這些屬性

為量子世界裡精巧易碎的異域物質

and remarkable characteristics to some exotic phases of matter

帶來驚人的穩定性

in the delicate quantum world.

One example is called a topological insulator.

一個例子叫做「拓撲絕緣體」

Imagine a film of electrons.

想像電子的影片

If a strong enough magnetic field passes through them,

如果夠強的磁場穿過這些電子

each electron will start traveling in a circle,

每個電子將開始繞圈圈

which is called a closed orbit.

稱為封閉的軌道

Because the electrons are stuck in these loops,

因為電子卡在圈圈中

they're not conducting electricity.

它們不導電

But at the edge of the material,

但在材料的邊緣

the orbits become open, connected, and they all point in the same direction.

軌道變得開放、連接 全都指向同一個方向

So electrons can jump from one orbit to the next

所以電子可以從一軌道跳到另一軌道

and travel all the way around the edge.

一路沿著邊緣繞行

This means that the material conducts electricity around the edge

這意味著材料的邊緣導電

but not in the middle.

但中間不導電

Here's where topology comes in.

這是用到拓撲學的地方

This conductivity isn't affected by small changes in the material,

導電不受微小材料變化的影響

like impurities or imperfections.

像是雜質或瑕疵

That's just like how the hole in the coffee cup

那就像咖啡杯那個洞

isn't changed by stretching it out.

不會因伸展而改變

The edge of such a topological insulator has perfect electron transport:

電子在拓撲絕緣體的邊緣完美地傳導

no electrons travel backward,

沒有電子會反向移動

no energy is lost as heat,

沒有能量以熱能的形式流失

and the number of conducting pathways can even be controlled.

還能控制共有幾條導電的途徑

The electronics of the future could be built

未來的電子產品

to use this perfectly efficient electron highway.

可以用這效率完美的電子公路來建造

The topological properties of subatomic particles

亞原子粒子的拓撲性質

could also transform quantum computing.

也可以改變量子計算

Quantum computers take advantage of the fact

量子計算機利用

that subatomic particles can be in different states at the same time

亞原子粒子能夠同時 處在不同狀態的事實

to store information in something called qubits.

存儲「量子位元」這信息

These qubits can solve problems exponentially faster

量子位元運算解題的速度

than classical digital computers.

是傳統數位電腦速度的指數級倍

The problem is that this data is so delicate

問題是這數據位元如此纖巧易碎

that interaction with the environment can destroy it.

與環境相互作用會摧毀它

But in some exotic topological phases,

但在一些奇特的拓撲階段

the subatomic particles can become protected.

亞原子粒子會受到保護

In other words, the qubits formed by them

換句話說，它們形成的量子位元

can't be changed by small or local disturbances.

不會受到小的或附近的干擾

These topological qubits would be more stable,

這些拓撲量子位元會更穩定

leading to more accurate computation and a better quantum computer.

導引出更精確的計算 和更好的量子計算機

Topology was originally studied as a branch of purely abstract mathematics.

最初的拓撲研究 是純抽像數學的一個分支

Thanks to the pioneering work of Thouless, Haldane, and Kosterlitz,

感謝杜列斯、哈爾丹 和科斯特利茲開拓性的研究

we now know it can be used to understand the riddles of nature

我們現在知道可以 用它來理解大自然的謎語

and to revolutionize the future of technologies.

並推進未來革命性的技術