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  • Translator: Morton Bast Reviewer: Thu-Huong Ha

    在這瞬間你看到的現象,

  • The phenomenon you saw here for a brief moment

    稱作量子懸浮和量子鎖定。

  • is called quantum levitation and quantum locking.

    而這個懸浮中的物體

  • And the object that was levitating here

    是超導體。

  • is called a superconductor.

    超導現象是物質的量子物理狀態,

  • Superconductivity is a quantum state of matter,

    它只會在低於特定的溫度時發生。

  • and it occurs only below a certain critical temperature.

    其實超導體現象存在已久;

  • Now, it's quite an old phenomenon;

    大約在一百年前就被發現了。

  • it was discovered 100 years ago.

    不過,

  • However, only recently,

    依賴於最近的技術進步 (譯按:是說高溫超導體)

  • due to several technological advancements,

    我們才可以在此展示

  • we are now able to demonstrate to you

    量子懸浮和量子鎖定。

  • quantum levitation and quantum locking.

    超導體具有兩種特徵。

  • So, a superconductor is defined by two properties.

    其一是零電阻,

  • The first is zero electrical resistance,

    其二是內部抗磁性。

  • and the second is the expulsion of a magnetic field from the interior of the superconductor.

    聽起來很複雜,對嗎?

  • That sounds complicated, right?

    何謂電阻?

  • But what is electrical resistance?

    電力是電子在物質中流動,

  • So, electricity is the flow of electrons inside a material.

    電子流動時會與原子碰撞,

  • And these electrons, while flowing,

    而這些碰撞

  • they collide with the atoms, and in these collisions

    會使電子失去部份能量

  • they lose a certain amount of energy.

    失去的能量會轉換成為熱,此謂之電阻

  • And they dissipate this energy in the form of heat, and you know that effect.

    可是,在超導體中不會有此類碰撞,

  • However, inside a superconductor there are no collisions,

    於是沒有能量流失。

  • so there is no energy dissipation.

    這相當不平常。試想想。

  • It's quite remarkable. Think about it.

    在古典物理學界,摩擦與能量流失無處不在。

  • In classical physics, there is always some friction, some energy loss.

    但因為這是量子物理現象,所以不存在摩擦和能量損失。

  • But not here, because it is a quantum effect.

    除此之外,因為超導體不喜歡磁場,

  • But that's not all, because superconductors don't like magnetic fields.

    超導體會通過使電流循環流動,

  • So a superconductor will try to expel magnetic field from the inside,

    而從其內部盡量把磁場排除。

  • and it has the means to do that by circulating currents.

    具備以上兩種特徵,

  • Now, the combination of both effects --

    零電阻和內部抗磁性,

  • the expulsion of magnetic fields and zero electrical resistance --

    就是超導體。

  • is exactly a superconductor.

    大家知道,事情並不總是完美的,

  • But the picture isn't always perfect, as we all know,

    有時候,一點點磁場會殘留在超導體內部。

  • and sometimes strands of magnetic field remain inside the superconductor.

    在適當的條件下,就如這裡可見,

  • Now, under proper conditions, which we have here,

    這些殘留的磁場會被困在超導體裡。

  • these strands of magnetic field can be trapped inside the superconductor.

    而且這些殘留的磁場是離散量,

  • And these strands of magnetic field inside the superconductor,

    即不是連續的。

  • they come in discrete quantities.

    為什麼? 因為這是量子現象,量子物理。

  • Why? Because it is a quantum phenomenon. It's quantum physics.

    它的行為就如量子一樣。

  • And it turns out that they behave like quantum particles.

    從影片可見,它一個個分開地移動。

  • In this movie here, you can see how they flow one by one discretely.

    它是磁場,而非粒子,

  • This is strands of magnetic field. These are not particles,

    但行為就如粒子一樣。

  • but they behave like particles.

    這就是為什麼這個現象叫量子懸浮和量子鎖定。

  • So, this is why we call this effect quantum levitation and quantum locking.

    若將超導體置入一個磁場中會發生甚麼事呢?

  • But what happens to the superconductor when we put it inside a magnetic field?

    嗯,首先是我們知道還有一些游離的磁場殘留在其中,

  • Well, first there are strands of magnetic field left inside,

    但是超導體不會讓他們隨便移動

  • but now the superconductor doesn't like them moving around,

    因為移動就會有能量流失,

  • because their movements dissipate energy,

    也就是說會破壞超導狀態。

  • which breaks the superconductivity state.

    所以超導體此時就會將這幾束所謂的磁通量子(磁場束)鎖定

  • So what it actually does, it locks these strands,

    將其固定在一個位置上

  • which are called fluxons, and it locks these fluxons in place.

    如此一來,超導體自己也會被固定住。

  • And by doing that, what it actually does is locking itself in place.

    為什麼呢?因為超導體的任何移動 都會改變這些磁通量子的位置,

  • Why? Because any movement of the superconductor will change their place,

    也就改變了其格局。

  • will change their configuration.

    這就是量子鎖定的由來。現在就讓我們來一探究竟,

  • So we get quantum locking. And let me show you how this works.

    現在我這裡有一個超導體, 事前已經用液氮包了起來, 這樣它可以保持在低溫的狀態足夠久。

  • I have here a superconductor, which I wrapped up so it'd stay cold long enough.

    當我將它放置在一個一般的磁鐵上時,

  • And when I place it on top of a regular magnet,

    它就這樣鎖定在半空中。

  • it just stays locked in midair.

    (掌聲)

  • (Applause)

    現在,這既不僅是懸浮,也不僅是排斥作用。

  • Now, this is not just levitation. It's not just repulsion.

    我可以改變這些磁通量子的位置,它會被鎖定在新的格局裡。

  • I can rearrange the fluxons, and it will be locked in this new configuration.

    就像這樣,或者是讓它偏左或偏右一點。

  • Like this, or move it slightly to the right or to the left.

    這就是量子鎖定--真正的鎖定--超導體的三維鎖定。

  • So, this is quantum locking -- actually locking -- three-dimensional locking of the superconductor.

    當然,我也可以把這個鎖定的格局翻過來,

  • Of course, I can turn it upside down,

    超導體仍然被鎖定在原來的位置。

  • and it will remain locked.

    現在我們已經知道所謂的懸浮其實是鎖定,

  • Now, now that we understand that this so-called levitation is actually locking,

    對,我們確實知道。

  • Yeah, we understand that.

    不難想像,如果我用一個各面磁場都均一

  • You won't be surprised to hear that if I take this circular magnet,

    的環狀磁鐵(來鎖定超導體),

  • in which the magnetic field is the same all around,

    超導體會圍繞着這個磁鐵的中軸自由旋轉。

  • the superconductor will be able to freely rotate around the axis of the magnet.

    為什麼?因為只要超導體保持旋轉, 就可以維持鎖定的狀態。

  • Why? Because as long as it rotates, the locking is maintained.

    看到了嗎?我也可以調節,也可以轉超導體。

  • You see? I can adjust and I can rotate the superconductor.

    這是沒有磨擦力的運動。仍然是懸浮, 但是(超導體)可以自由地移動。

  • We have frictionless motion. It is still levitating, but can move freely all around.

    這就是量子鎖定,而我們可以讓超導體懸浮在磁鐵的上方。

  • So, we have quantum locking and we can levitate it on top of this magnet.

    不過,這樣一個圓盤到底有多少磁通量子,多少磁場條呢?

  • But how many fluxons, how many magnetic strands are there in a single disk like this?

    嗯,我們可以計算出來,結果是,非常多。

  • Well, we can calculate it, and it turns out, quite a lot.

    在這個3英寸直徑的圓盤裡,有100億條磁場。

  • One hundred billion strands of magnetic field inside this three-inch disk.

    這還不是最驚人的部分,因為最驚人的我還沒告訴你。

  • But that's not the amazing part yet, because there is something I haven't told you yet.

    最驚人的是,這個你現在看到的超導體,

  • And, yeah, the amazing part is that this superconductor that you see here

    只有一微米厚,非常地薄。

  • is only half a micron thick. It's extremely thin.

    而這個超薄的超導體可以 懸浮起其自身重量70,000倍的物體。

  • And this extremely thin layer is able to levitate more than 70,000 times its own weight.

    這是非常不尋常的事。它非常強壯。

  • It's a remarkable effect. It's very strong.

    接下來,我把這個環形的磁鐵延伸,

  • Now, I can extend this circular magnet,

    把它做成任何我想要的軌道。

  • and make whatever track I want.

    比如說,我可以做一個像這樣的大圓環軌道。

  • For example, I can make a large circular rail here.

    然後,當我把這個超導體圓盤放到軌道上方時,

  • And when I place the superconducting disk on top of this rail,

    它會自由地(沿著軌道)移動。

  • it moves freely.

    (掌聲)

  • (Applause)

    而且,除此之外,我還可以調節它的位置,像這樣,然後旋轉,

  • And again, that's not all. I can adjust its position like this, and rotate,

    它仍會在其新的位置上自由移動。

  • and it freely moves in this new position.

    我甚至可以試試我還沒有試過的變化;

  • And I can even try a new thing; let's try it for the first time.

    我可以把這個超導體放在這裡,

  • I can take this disk and put it here,

    在它鎖定後--別動--

  • and while it stays here -- don't move --

    我要試著把這個磁鐵軌道翻過來,

  • I will try to rotate the track,

    希望,如果我沒錯的話,

  • and hopefully, if I did it correctly,

    它會仍然懸浮。

  • it stays suspended.

    (掌聲)

  • (Applause)

    各位,這就是量子鎖定,不是懸浮。

  • You see, it's quantum locking, not levitation.

    接下來,在它繼續轉的時候,

  • Now, while I'll let it circulate for a little more,

    我要再告訴你一些關於超導體的其他事情。

  • let me tell you a little bit about superconductors.

    現在--(笑聲)--

  • Now -- (Laughter) --

    我們現在知道我們可以在超導體內傳導巨大的電流,

  • So we now know that we are able to transfer enormous amount of currents inside superconductors,

    我們可以用超導體來產生強大的磁場,

  • so we can use them to produce strong magnetic fields,

    如磁共振成像儀,粒子加速器等所需的巨大磁場。

  • such as needed in MRI machines, particle accelerators and so on.

    我們也可以用超導體儲存能量,

  • But we can also store energy using superconductors,

    因為沒有能量耗散。

  • because we have no dissipation.

    我們也可以用超導體製造電纜,在電站間運送電流。

  • And we could also produce power cables, to transfer enormous amounts of current between power stations.

    想像一下,你可以用一根超導電纜來給一整個電站供電。

  • Imagine you could back up a single power station with a single superconducting cable.

    那麼,量子懸浮和量子鎖定的未來是什麼?

  • But what is the future of quantum levitation and quantum locking?

    嗯,讓我舉個例子來回答這個簡單的問題。

  • Well, let me answer this simple question by giving you an example.

    想像你有像我這樣的一個圓盤在手裡,

  • Imagine you would have a disk similar to the one I have here in my hand,

    3英寸直徑,唯一不同的是,

  • three-inch diameter, with a single difference.

    這個超導片不是一微米厚,

  • The superconducting layer, instead of being half a micron thin,

    而是兩毫米厚,仍然很薄。

  • being two millimeters thin, quite thin.

    這個兩毫米厚的超導片可以 在我手裡舉起1000公斤,一輛小車。

  • This two-millimeter-thin superconducting layer could hold 1,000 kilograms, a small car, in my hand.

    很驚人吧。謝謝

  • Amazing. Thank you.

    (掌聲)

  • (Applause)

Translator: Morton Bast Reviewer: Thu-Huong Ha

在這瞬間你看到的現象,

字幕與單字

影片操作 你可以在這邊進行「影片」的調整,以及「字幕」的顯示

B2 中高級 中文 TED 量子 鎖定 磁場 磁鐵 能量

【TED】博阿斯-阿爾莫格 "懸浮 "超導體。 (【TED】Boaz Almog "levitates" a superconductor)

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