The movable mask was placed behind the double-slit, see figure 1. The mask was moved from one side to the other (figure 2 top to bottom). Initially the majority of the electrons are blocked. As the mask is moved, slit 1 becomes partially, then fully open. When one slit is open, single- slit diffraction can be observed (P1 in figures 1(b) and 2). Feynman indicates this as the solid black curve P1 (figure 1(b)), which is just the central order of the single-slit diffraction pattern. Because of the finite separation of the mask and double-slit, weak double-slit diffraction can be seen in the negative first order of the single-slit diffraction pattern (see left edge of P1 in figure 2).
As the mask is moved further, more electrons can travel through both slits, changing the pattern from single-slit to double-slit diffraction. When the mask is centered on the double-slit, both slits are completely open and full double-slit diffraction can be observed (P12 in figures 1(c) and 2). In this position, interaction between the mask and the diffracting electrons is negligible. The edges of the mask are 2250 nm away from the center and would only affect diffraction orders greater than the 50th. The mask is then moved further and the reverse happens; double- slit diffraction changes back to single-slit diffraction (P2 in figures 1(b) and 2). Now, the single- slit diffraction pattern has a weak contribution of double-slit diffraction in its positive first order (see right edge of P2 in figure 2). (See supplementary movie 1 for more positions of the mask.)
Electron build-up patterns were recorded with the mask centered on the double-slit. The electron source’s intensity was reduced so that the electron detection rate in the pattern was about 1 Hz. At this rate and kinetic energy, the average distance between consecutive electrons was 2.3 × 10^6 m.
這篇文章的電子版在這裏：http://iopscience.iop.org/article/10.1088/1367-2630/15/3/033018/pdf
下麵三段文字，說明了滑動屏幕實驗中包含了單縫的結果。而電子束的強度減到非常弱，可以認為電子是i一個個分開發射出來的。
The movable mask was placed behind the double-slit, see figure 1. The mask was moved from one side to the other (figure 2 top to bottom). Initially the majority of the electrons are blocked. As the mask is moved, slit 1 becomes partially, then fully open. When one slit is open, single- slit diffraction can be observed (P1 in figures 1(b) and 2). Feynman indicates this as the solid black curve P1 (figure 1(b)), which is just the central order of the single-slit diffraction pattern. Because of the finite separation of the mask and double-slit, weak double-slit diffraction can be seen in the negative first order of the single-slit diffraction pattern (see left edge of P1 in figure 2).
As the mask is moved further, more electrons can travel through both slits, changing the pattern from single-slit to double-slit diffraction. When the mask is centered on the double-slit, both slits are completely open and full double-slit diffraction can be observed (P12 in figures 1(c) and 2). In this position, interaction between the mask and the diffracting electrons is negligible. The edges of the mask are 2250 nm away from the center and would only affect diffraction orders greater than the 50th. The mask is then moved further and the reverse happens; double- slit diffraction changes back to single-slit diffraction (P2 in figures 1(b) and 2). Now, the single- slit diffraction pattern has a weak contribution of double-slit diffraction in its positive first order (see right edge of P2 in figure 2). (See supplementary movie 1 for more positions of the mask.)
Electron build-up patterns were recorded with the mask centered on the double-slit. The electron source’s intensity was reduced so that the electron detection rate in the pattern was about 1 Hz. At this rate and kinetic energy, the average distance between consecutive electrons was 2.3 × 10^6 m.
Controlled double-slit electron diffraction
Roger Bach, Damian Pope, Sy-Hwang Liou, Herman Batelaan
對“光束”和“電子束”的實驗沒有任何疑義，但是找不到“單個”光子或者“單個”電子做兩次單縫實驗得到的疊加結果。
回複 'LingYuan' 的評論 : 謝謝淩遠兄。我這幾年主要時間在寫科普。我記得你寫的詩和詩評呢，特別是評天端的詩。一晃差不多十年了。
量子世界一個基本特性是測不準的特性。隨著對量子世界越來越多的認識，這種說法似乎值得商榷。因為說測不準的隱含之意是被測物是確定的 隻是不能準確測出來。現在看來量子世界本身就是不確定的。
你的雙縫實驗科普寫得很好，既有來龍又有去脈 條理清晰 深入淺出。從小小的雙縫 把量子世界洞察得非常清晰。
水分子運動， 應該是布朗運動吧。
“大樣本觀察的話都是波粒二象的，單個就是粒，整體就是波“，波粒二象倒並不是按”單個／整體“來區分的。宏觀物體的波動性很小，幾乎不可察覺。而微觀物體的波動、粒子特性都可觀測到，但是受互補原理的限製，隻能同時觀察到其中之一，仿佛硬幣的兩麵，隻能看到一麵。
beaglegirl 發表評論於 2018-08-23 16:14:36
simplyu：讓我想起念書時流行的黃色歇後語，楊貴妃搞同性戀
--下半句是什麽？
--下半句是什麽？