The shortest distance between two points may be a straight line, but try telling that to electrons: when current flows down a wire, these particles zig and zag, moving indirectly from one end to the other. But now researchers have sped single ____1____ straight to their destinations using sound. The work is in the journal Nature. [Rob McNeil et al., "On-demand single-electron transfer between distant quantum dots"]

An electron’s quantum state carries information, making it important for a viable ____2____computer. As the particle staggers down a wire, however, its state loses coherence—the electron “forgets” the information it carried.

To make it travel more efficiently, researchers ____3____ a short burst of sound at an electron trapped in an energy well. The sound wave “l(fā)ifted” the electron, speeding it directly towards an empty well. Once it reached its destination, a sound burst from the opposite direction sent the electron back to its original location.

This discovery is a step toward quantum computing, which requires the controlled transfer of single electrons. But it could also have another ____4____ : electron ping-pong. Researchers have bounced an electron back and forth up to 60 times. Nice nano-rally.
【視聽版科學(xué)小組榮譽(yù)出品】
electrons quantum blasted application
也許兩點(diǎn)間直線最短，所以，科學(xué)家們想利用這個(gè)道理來(lái)做以下實(shí)驗(yàn)：當(dāng)電流劃過(guò)一根電線時(shí)，小電子們磕磕絆絆幾經(jīng)周折才由一頭流向另一頭，那么科學(xué)家們就想利用聲波將單電子加速，讓它們以直線從一頭運(yùn)動(dòng)到另一頭。這項(xiàng)實(shí)驗(yàn)著作已經(jīng)在《自然》期刊上發(fā)表?！綬ob McNeil等人，“受控單電子在量子點(diǎn)間的移動(dòng)”】 一個(gè)電子的量子態(tài)攜帶著信息，這對(duì)制造量子計(jì)算機(jī)是十分重要的。當(dāng)電子在電線上移動(dòng)時(shí)，會(huì)失去其連貫性——也就是說(shuō)，他們?cè)谶\(yùn)動(dòng)過(guò)程中丟失了所攜帶的信息。 為了使電子的運(yùn)動(dòng)效率提高，研究者對(duì)困在勢(shì)中的電子加了一個(gè)短促的沖擊聲波。這個(gè)聲波推動(dòng)電子，使電子沿著空勢(shì)阱直線加速。每次電子到達(dá)重點(diǎn)，反方向的沖擊聲波又會(huì)把電子送回出發(fā)點(diǎn)。 這項(xiàng)發(fā)現(xiàn)是量子計(jì)算旅程的驛站，研究中更需要控制單電子的移動(dòng)。不過(guò)它也有另一項(xiàng)用途：電子乒乓球。研究者已經(jīng)能讓一個(gè)電子進(jìn)行60次上下彈跳，真是不錯(cuò)的納米拉力賽。