北京時間10月4日下午5點49分許,瑞典皇家科學院決定将2022年的諾貝爾物理學獎授予法國科學家Alain Aspect、美國科學家John F.Clauser和奧地利科學家Anton Zeilinger ,以表彰他們“用糾纏光子進行的實驗,建立了貝爾不等式的違反,并開創了量子信息科學”。
2022年的諾貝爾獎單項獎金為1000萬瑞典克朗(約合人民币642.8萬元)。
糾纏态——從理論到技術
Alain Aspect、John Clauser和Anton Zeilinger都用糾纏量子态進行了開創性的實驗。在糾纏量子态中,即使兩個粒子分離,它們也表現得像一個單獨的單元。他們的研究結果為基于量子信息的新技術掃清了道路。
量子力學的不可言說的效應開始得到應用。現在有一個很大的研究領域,包括量子計算機、量子網絡和安全的量子加密通信。
這一進展的一個關鍵因素是,量子力學如何允許兩個或多個粒子以所謂的糾纏态存在。糾纏對中的一個粒子發生的情況決定了另一個粒子發生的情況,即使它們相距很遠。
在很長一段時間裡,問題在于這種相關性是否是因為糾纏對中的粒子包含隐藏變量,即告訴它們在實驗中應該給出哪個結果的指令。20世紀60年代,John Stewart Bell提出了以他的名字命名的數學不等式。這表明,如果存在隐藏變量,那麼大量測量結果之間的相關性将永遠不會超過某個值。然而,量子力學預測,某種類型的實驗将違反貝爾不等式,從而産生比其他情況下更強的相關性。
John Clauser發展了John Bell的想法,導緻了一個實際的實驗。當他進行測量時,它們顯然違反了貝爾不等式,從而支持了量子力學。這意味着量子力學不能被使用隐變量的理論所取代。
在John Clauser的實驗之後,仍然存在一些漏洞。Alain Aspect開發了這個設置,用它堵住了一個重要的漏洞。他能夠在一個糾纏對離開它的源後切換測量設置,所以當它們被發射時存在的設置不會影響結果。
通過精密的工具和一系列的實驗,Anton Zeilinger開始使用糾纏量子态。此外,他的研究小組還展示了一種被稱為量子隐形傳态的現象,這種現象使得量子态在一定距離内從一個粒子移動到另一個粒子成為可能。
“越來越明顯的是,一種新的量子技術正在出現。我們可以看到,獲獎者對糾纏态的研究非常重要,甚至超越了解釋量子力學的基本問題,”諾貝爾物理學委員會主席Anders Irbäck說。
Alain Aspect, John Clauser and Anton Zeilinger have each conducted groundbreaking experiments using entangled quantum states, where two particles behave like a single unit even when they are separated. Their results have cleared the way for new technology based upon quantum information.
The ineffable effects of quantum mechanics are starting to find applications. There is now a large field of research that includes quantum computers, quantum networks and secure quantum encrypted communication.
One key factor in this development is how quantum mechanics allows two or more particles to exist in what is called an entangled state. What happens to one of the particles in an entangled pair determines what happens to the other particle, even if they are far apart.
For a long time, the question was whether the correlation was because the particles in an entangled pair contained hidden variables, instructions that tell them which result they should give in an experiment. In the 1960s, John Stewart Bell developed the mathematical inequality that is named after him. This states that if there are hidden variables, the correlation between the results of a large number of measurements will never exceed a certain value. However, quantum mechanics predicts that a certain type of experiment will violate Bell’s inequality, thus resulting in a stronger correlation than would otherwise be possible.
John Clauserdeveloped John Bell’s ideas, leading to a practical experiment. When he took the measurements, they supported quantum mechanics by clearly violating a Bell inequality. This means that quantum mechanics cannot be replaced by a theory that uses hidden variables.
Some loopholes remained after John Clauser’s experiment.Alain Aspectdeveloped the setup, using it in a way that closed an important loophole. He was able to switch the measurement settings after an entangled pair had left its source, so the setting that existed when they were emitted could not affect the result.
Using refined tools and long series of experiments,Anton Zeilingerstarted to use entangled quantum states. Among other things, his research group has demonstrated a phenomenon called quantum teleportation, which makes it possible to move a quantum state from one particle to one at a distance.
“It has become increasingly clear that a new kind of quantum technology is emerging. We can see that the laureates’ work with entangled states is of great importance, even beyond the fundamental questions about the interpretation of quantum mechanics,” says Anders Irbäck, Chair of the Nobel Committee for Physics.
The illustrations are free to use for non-commercial purposes. Attribute ”© Johan Jarnestad/The Royal Swedish Academy of Sciences”.
Popular science background:
Scientific Background:photons, establishing the violation of Bell inequalities and pioneering quantum information science” (pdf)
諾獎得主簡介
Alain Aspect,1947年出生于法國阿根。1983年從法國奧賽巴黎-南德大學獲得博士學位。目前為法國巴黎薩克萊大學和帕萊索理工學院教授。
John F. Clauser,1942年出生于美國加州帕薩迪納。1969年獲得美國紐約哥倫比亞大學博士學位。
Anton Zeilinger,1945年出生于奧地利裡德伊姆·因克瑞斯。1971年獲得奧地利維也納大學博士學位。目前為維也納大學教授。
過去6年諾貝爾物理學獎得主名單
2020年,Roger Penrose,獲獎理由是發現黑洞的形成是對廣義相對論的有力預測;Reinhard Genzel及Andrea Ghez獲獎理由是在銀河系中心發現了一個超大質量的緻密天體。
2019年,美國科學家James Peebles獲獎,獲獎理由是“在物理宇宙學的理論發現”;另外兩位獲獎者是瑞士科學家Michel Mayor和Didier Queloz,獲獎理由是“發現了一顆圍繞類太陽恒星運行的系外行星”。
2018年,美法加三位科學家Arthur Ashkin、Gerard Mourou和Donna Strickland獲獎,獲獎理由是“在激光物理學領域所作出的開創性發明”。
2017年,三位美國科學家Rainer Weiss、Barry C. Barish和Kip S. Thorne獲獎,獲獎理由是“對LIGO探測器和引力波觀測的決定性貢獻”。
2016年,英美三位科學家David J. Thouless、F. Duncan M. Haldane、J. Michael Kosterlitz獲獎,獲獎理由是“理論發現拓撲相變和拓撲相物質”。
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