科學(xué)60秒:高科技快遞派送小電子
來源：滬江聽寫酷
2011-10-09 10:00
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)小組榮譽出品】
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)小組榮譽出品】
electrons quantum blasted application
也許兩點間直線最短，所以，科學(xué)家們想利用這個道理來做以下實驗：當(dāng)電流劃過一根電線時，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動到另一頭。這項實驗著作已經(jīng)在《自然》期刊上發(fā)表?！綬ob McNeil等人，“受控單電子在量子點間的移動”】 一個電子的量子態(tài)攜帶著信息，這對制造量子計算機是十分重要的。當(dāng)電子在電線上移動時，會失去其連貫性——也就是說，他們在運動過程中丟失了所攜帶的信息。 為了使電子的運動效率提高，研究者對困在勢中的電子加了一個短促的沖擊聲波。這個聲波推動電子，使電子沿著空勢阱直線加速。每次電子到達(dá)重點，反方向的沖擊聲波又會把電子送回出發(fā)點。 這項發(fā)現(xiàn)是量子計算旅程的驛站，研究中更需要控制單電子的移動。不過它也有另一項用途：電子乒乓球。研究者已經(jīng)能讓一個電子進(jìn)行60次上下彈跳，真是不錯的納米拉力賽。
