Pamtima pa quantum mechanics

Richard Feynman, mmodzi mwa akatswiri a sayansi ya zakuthambo m'zaka za zana la 19, adanena kuti chinsinsi chomvetsetsa makina a quantum chinali "kuyesera kawiri kawiri." Kuyesera kosavuta kumeneku, komwe kukuchitika masiku ano, kukupitilizabe kutulutsa zinthu zodabwitsa. Amawonetsa momwe makina a quantum samayenderana ndi nzeru wamba, zomwe zidapangitsa kuti pakhale zinthu zofunika kwambiri pazaka makumi asanu zapitazi.

Anayesa magawo awiri kwa nthawi yoyamba. Thomas Young (1) ku England kumayambiriro kwa zaka za zana la khumi ndi zisanu ndi zinayi.

kuyesa kwa Yang

Kuyeseraku kudagwiritsidwa ntchito kusonyeza kuti kuwala ndi kwachilengedwe kozungulira osati kwa tinthu tating'ono, monga momwe adanenera kale. Isaac Newton. Achinyamata anangosonyeza kuti kuwala kumamvera kulowererapo - chodabwitsa chomwe chimakhala chodziwika kwambiri (mosasamala mtundu wa mafunde ndi sing'anga yomwe imafalikira). Masiku ano, makina a quantum amagwirizanitsa malingaliro onsewa otsutsana.

Tiyeni tikumbukire chiyambi cha kuyesa kwa magawo awiri. Monga mwachizolowezi, ndikunena za mafunde a pamwamba pa madzi omwe amayenda molunjika pamalo pomwe mwalawu umaponyedwa. 

Mafunde amapangidwa ndi ma crests otsatizana ndi mikwingwirima yotuluka kuchokera pamalo osokonekera, ndikusunga mtunda wokhazikika pakati pa ma crests, otchedwa wavelength. Panjira ya mafunde, mutha kuyika chotchinga, mwachitsanzo, ngati bolodi yokhala ndi timizere tating'ono tating'onoting'ono tomwe madzi amatha kuyenda momasuka. Ataponya mwala m'madzi, fundelo limayima pagawo - koma osati kwenikweni. Mafunde awiri okhazikika (2) tsopano akufalikira mbali ina ya magawano kuchokera kumagawo onse awiri. Amaphatikizana, kapena, monga tikunenera, amasokonezana, ndikupanga mawonekedwe apamwamba. M'malo omwe chiwombankhanga cha funde limodzi chimakumana ndi nsonga ya funde lina, madziwo amakulirakulira, ndipo pamene dzenje limakumana ndi chigwa, kupsinjika maganizo kumakula.

2. Kusokoneza kwa mafunde omwe akutuluka kuchokera ku ma slits awiri.

Mukuyesera kwa Young, kuwala kwamtundu umodzi komwe kumachokera kumalo komwe kumadutsa mumzere wosawoneka bwino wokhala ndi ting'onoting'ono tiwiri ndikugunda pazenera kumbuyo kwawo (lero tingakonde kugwiritsa ntchito kuwala kwa laser ndi CCD). Chithunzi chosokoneza cha mafunde a kuwala chimawonedwa pazenera ngati mawonekedwe a mikwingwirima yosinthasintha ndi mikwingwirima yakuda (3). Chotsatira ichi chinalimbitsa chikhulupiriro chakuti kuwala kunali mafunde, asanatulutsidwe kumayambiriro kwa zaka za m'ma XNUMX anasonyeza kuti kuwala kunalinso mafunde. photon flux - tinthu zopepuka zomwe zilibe mpumulo. Kenako zinapezeka kuti zachinsinsi wave-particle dualitykutulukira koyamba kwa kuwala, kumagwiranso ntchito ku tinthu ting'onoting'ono tomwe tapatsidwa unyinji. Posakhalitsa idakhala maziko a kufotokozera kwatsopano kwamakina a dziko lapansi.

3. Masomphenya a Young pakuyesera

Tinthu timasokonezanso

Mu 1961, Klaus Jonsson wochokera ku yunivesite ya Tübingen adawonetsa kusokonezedwa kwa tinthu tating'onoting'ono totchedwa ma elekitironi pogwiritsa ntchito maikulosikopu ya elekitironi. Zaka khumi pambuyo pake, akatswiri atatu a sayansi ya zakuthambo aku Italy ochokera ku yunivesite ya Bologna adayesanso chimodzimodzi kusokoneza kwa elekitironi imodzi (kugwiritsa ntchito chotchedwa biprism m'malo mwa kang'ono kawiri). Anachepetsa mphamvu ya mtengo wa elekitironi kukhala wotsika kwambiri kotero kuti ma elekitironi amadutsa mu biprism imodzi ndi imodzi, imodzi pambuyo pa inzake. Ma electron awa analembedwa pa nsalu yotchinga fulorosenti.

Poyamba, mawonekedwe a ma elekitironi adagawidwa mwachisawawa pazenera, koma pakapita nthawi adapanga chithunzi chowoneka bwino cha zosokoneza. Zikuwoneka kuti sizingatheke kuti ma elekitironi awiri akudutsa motsatizana podutsa nthawi zosiyanasiyana akhoza kusokonezana. Choncho tiyenera kuvomereza zimenezo electron imodzi imasokoneza yokha! Koma ndiye kuti elekitironi iyenera kudutsa m'mipata yonseyi nthawi imodzi.

Zingakhale zokopa kuyang'ana dzenje lomwe electron inadutsamo. Tidzawona pambuyo pake momwe tingapangire izi popanda kusokoneza kayendedwe ka electron. Zikuwonekeratu kuti ngati tilandira chidziwitso chomwe electron yavomereza, ndiye kuti kusokoneza ... kudzatha! "Momwe" chidziwitso chimathetsa kusokoneza. Kodi izi zikutanthauza kuti kukhalapo kwa wopenyerera wozindikira kumakhudza kachitidwe ka thupi?

Ndisanalankhule za zotsatira zodabwitsa kwambiri za kuyesa kwa magawo awiri, ndipanga pang'onopang'ono za kukula kwa zinthu zosokoneza. Kusokoneza kwa Quantum kwa zinthu zambiri kunapezeka koyamba kwa ma elekitironi, kenako kwa tinthu tating'onoting'ono tomwe timachulukirachulukira: ma neutroni, ma protoni, ma atomu, ndipo pomaliza ndi mamolekyu akulu amankhwala.

Mu 2011, mbiri ya kukula kwa chinthu chomwe chikuwonetsa chodabwitsa cha kusokoneza kwa quantum chinasweka. Kuyesera kunachitika ku yunivesite ya Vienna ndi wophunzira wa udokotala panthawiyo. Sandra Eibenberger ndi abwenzi ake. Pakuyesa kwapawiri, molekyu yovuta kwambiri yokhala ndi ma protoni pafupifupi 5, ma neutroni 5 ndi ma electron 5! Mu kuyesa kovutirapo kwambiri, kusokoneza kwa quantum kwa molekyulu yayikuluyi kudawonedwa.

Izi zinatsimikizira chikhulupiriro chakuti Osati zinthu zoyambira zokha, komanso chinthu chilichonse chakuthupi chimamvera malamulo a quantum mechanics. Kungoti chinthucho chimakhala chovuta kwambiri, chimagwirizana kwambiri ndi chilengedwe chake, chomwe chimaphwanya katundu wake wobisika wa quantum ndikuwononga zotsatira zosokoneza..

Quantum entanglement ndi polarization ya kuwala

Zotsatira zodabwitsa kwambiri za kuyesa kwawiri-slit zinachokera ku kugwiritsa ntchito njira yapadera yotsata chithunzithunzi, chomwe sichinasokoneze kuyenda kwake mwanjira iliyonse. Njirayi imagwiritsa ntchito chimodzi mwazinthu zodabwitsa kwambiri za quantum, zomwe zimatchedwa quantum entanglement. Chodabwitsa ichi chidadziwika m'zaka za m'ma 30 ndi m'modzi mwa omwe adapanga makina a quantum mechanics, Erwin Schrödinger.

Wokayikira Einstein (onaninso 🙂) adawatcha kuti "ghostly action" patali.Komabe, patatha theka la zaka kufunikira kwa izi kunazindikirika, ndipo lero wakhala nkhani yosangalatsa kwambiri kwa akatswiri a sayansi ya zakuthambo.

Kodi zotsatira zake ndi zotani? Ngati tinthu ting'onoting'ono tomwe tinkayandikana nthawi imodzi tidalumikizana mwamphamvu kwambiri mpaka tidapanga mtundu wa "ubwenzi wamapasa," ndiye kuti ubalewu umagwira ngakhale tinthu tating'ono tating'ono ta makilomita mazanamazana. Ndiye particles amachita ngati dongosolo limodzi. Izi zikutanthauza kuti tikachita kanthu pa tinthu tating'onoting'ono, timakhudza gawo lina. Komabe, mwanjira imeneyi sitingathe kufalitsa uthenga patali mosayembekezereka.

Photon ndi tinthu tambirimbiri - gawo loyambirira la kuwala, lomwe ndi mafunde amagetsi. Atadutsa m'mbale ya kristalo yofananira (yotchedwa polarizer), kuwalako kumakhala polarized polarized, i.e. gwero lamagetsi lamagetsi la electromagnetic wave oscillates mu ndege inayake. Nayenso, podutsa kuwala kozungulira mozungulira mu mbale ya makulidwe ena kuchokera ku kristalo wina (yomwe imatchedwa mbale ya quarter wave), imatha kusinthidwa kukhala kuwala kozungulira, komwe vekitala yamagetsi imayenda mu helical ( clockwise kapena counterclockwise) kuyenda motsatira njira yofalitsa mafunde. Choncho, tikhoza kulankhula za linearly kapena circularly polarized photon.

Kuyesera ndi mafotoni omangika

4 a. BBO crystal yopanda mzere imatembenuza chithunzithunzi chopangidwa ndi argon laser kukhala mafotoni awiri omangika okhala ndi theka la mphamvu komanso polarization yolumikizana. Zithunzizi zimabalalika m'njira zosiyanasiyana ndipo zimalembedwa ndi zowunikira D1 ndi D2, zolumikizidwa ndi LC coincidence counter. Zowunikira zonse zikazindikira kufika pafupifupi munthawi yomweyo mafotoni onse awiri, chizindikirocho chimasungidwa m'chikumbukiro cha chipangizocho, ndipo chowunikira D2 chimayenda mofananira ndi ma slits. Chiwerengero cha ma photon monga ntchito ya malo a detector D2 olembedwa motere akuwonetsedwa mu bokosi, kusonyeza maxima ndi minima kusonyeza kusokoneza.

Mu 2001, gulu la akatswiri a sayansi ya ku Brazil ku Belo Horizonte linatsogolera Stephen Walbourn kuyesa kwachilendo. Olemba ake adagwiritsa ntchito zida za kristalo yapadera (yofupikitsidwa BBO), yomwe imasintha gawo lina la zithunzi zomwe zimatulutsidwa ndi laser ya argon kukhala zithunzi ziwiri ndi theka la mphamvu. Ma photon awiriwa amamangiriridwa wina ndi mzake; pamene mmodzi wa iwo ali, mwachitsanzo, yopingasa polarization, winayo vertical polarization. Ma photon awa amayenda mbali ziwiri zosiyana ndikugwira ntchito zosiyanasiyana pakuyesera komwe kukufotokozedwa.

Imodzi mwamafotoni omwe tiyitanira kulamulira, amapita molunjika ku chojambulira cha photon D1 (4a). Chowunikira chimalembetsa kubwera kwake potumiza chizindikiro chamagetsi ku chipangizo chotchedwa coincidence counter. LK Kuyesera kosokoneza kudzachitidwa pa photon yachiwiri; tidzamuyitana iye chizindikiro cha photon. M'njira yake pali mipata iwiri yotsatiridwa ndi chojambulira chachiwiri cha photon D2, chotalikirapo pang'ono kuchokera ku gwero la photon kuposa chowunikira D1. Chodziwira ichi chimatha kulumpha malo ake molingana ndi malo olowera pawiri nthawi iliyonse chikalandira chizindikiro chofananira kuchokera kokauntala mwangozi. Chojambulira D1 chikazindikira chithunzithunzi, chimatumiza chizindikiro ku counter coincidence counter. Ngati, pakapita nthawi, chowunikira D2 chimazindikiranso chithunzithunzi ndikutumiza chizindikiro ku mita, chidzazindikira kuti chimachokera ku ma photon otsekedwa, ndipo izi zidzasungidwa mu kukumbukira kwa chipangizocho. Njirayi imathetsa kulembetsa kwa ma photon osasintha omwe amalowa mu chowunikira.

Zithunzi zomangika zimapitilira masekondi 400. Pambuyo pa nthawiyi, chojambulira cha D2 chimasinthidwa ndi 1 mm poyerekezera ndi malo a slits, ndipo kuwerengera ma photon otsekedwa kumatenga masekondi ena 400. Chowunikiracho chimasunthidwanso ndi 1 mm ndipo ndondomekoyi imabwerezedwa nthawi zambiri. Zikuoneka kuti kugawidwa kwa chiwerengero cha ma photon olembedwa motere kutengera malo a detector D2 ali ndi khalidwe maxima ndi minima lolingana ndi kuwala ndi mdima ndi zosokoneza mu kuyesera Young (4a).

Tizipezanso izo mafotoni amodzi omwe amadutsa mugawo lawiri amasokonezana.

Bwanji?

Chotsatira choyesera chinali kudziwa dzenje lomwe photon inayake ingadutse popanda kusokoneza kuyenda kwake. Katundu ntchito pano mbale ya quarter wave. Mbale yozungulira kotala inayikidwa kutsogolo kwa kang'ono kalikonse, komwe kunkasintha mzere wozungulira wa chithunzicho kukhala polarization yozungulira mozungulira, ndipo inayo kumanzere kumanzere (4b). Zinatsimikiziridwa kuti mtundu wa photon polarization sunakhudze chiwerengero cha ma photon owerengedwa. Tsopano, pozindikira kuzungulira kwa polarization ya chithunzi pambuyo podutsa m'mipata, tikhoza kusonyeza kuti ndi ndani mwa iwo omwe chithunzicho chinadutsamo. Kudziwa "kumene" kumathetsa kusokoneza.

4b . Poyika mbale za kotala-wave (makona amithunzi) kutsogolo kwa slits, chidziwitso chokhudza "njira" yomwe ingapezeke ndipo chithunzi chosokoneza chidzatha.

4c . Kuyika polarizer yolunjika bwino P kutsogolo kwa chowunikira D1 kumachotsa chidziwitso cha "njira iti" ndikubwezeretsa kusokoneza.

Kwenikweni, Pamene mbale za kotala-wave zimayikidwa bwino kutsogolo kwa slits, kugawidwa kowerengera komwe kunawonedwa kale komwe kukuwonetsa kusokoneza kumasowa. Chodabwitsa kwambiri ndi chakuti izi zimachitika popanda kutenga nawo mbali kwa wopenyerera wozindikira yemwe angathe kupanga miyeso yoyenera! Kungoyika mbale za kotala-wave kumabweretsa kusokoneza-kupondereza.. Ndiye kodi photon imadziwa bwanji kuti ikalowetsa mbalezo, tikhoza kudziwa kusiyana komwe idadutsa?

Komabe, awa si mapeto a zodabwitsa. Tsopano titha kukonzanso kusokoneza kwa chizindikiro cha photon popanda kukhudza mwachindunji. Kuti muchite izi, ikani polarizer munjira ya control photon yofikira detector D1 kuti ipereke kuwala ndi polarization yomwe imaphatikiza ma polarizations a mafotoni onse otsekeredwa (4c). Izi zimasintha nthawi yomweyo polarity ya chizindikiro cha photon moyenerera. Tsopano sikuthekanso kudziwa motsimikiza kuti polarization ya chochitika cha photon pa slits ndi chiyani, komanso momwe chithunzicho chinadutsa. Pankhaniyi, kusokoneza kumabwezeretsedwa!

Fufutani zambiri zochedwetsedwa

Zoyesera zomwe tafotokozazi zidachitika m'njira yoti photon yowongolera idazindikirika ndi detector D1 isanakwane chizindikiro cha D2. Kufufuta "njira yotani" chidziwitso chinakwaniritsidwa mwa kusintha polarization ya fotoni yoyendetsa galimoto isanafikire chowunikira D2. Ndiye munthu akhoza kuganiza kuti photon yolamulira yauza kale "mapasa" ake zomwe ayenera kuchita: kulowerera kapena ayi.

Tsopano tisintha kuyesera kotero kuti photon yowongolera igunda chowunikira D1 pambuyo polembetsa chizindikiro cha photon pa detector D2. Kuti muchite izi, chotsani chowunikira D1 kutali ndi gwero la fotoni. Njira yosokoneza ikuwoneka yofanana. Tsopano tiyeni tiyike mbale za quarter-wave kutsogolo kwa ming'alu kuti tidziwe njira yomwe photon yatenga. Njira yosokoneza imatha. Kenako, tiyeni tifufute za "njira iti" poyika polarizer yolunjika bwino kutsogolo kwa chowunikira D1. Njira yosokoneza ikuwonekeranso! Komabe kufufutidwa kunachitika pambuyo poti chizindikiro cha photon chizindikirike ndi detector D2. Kodi izi zingatheke bwanji? Photon iyenera kudziwa za kusintha kwa polarity musanadziwe zambiri za izo.

5. Kuyesera ndi mtengo wa laser.

Ndondomeko yachilengedwe ya zochitika pano yasinthidwa; zotsatira zimatsogolera chifukwa! Chotsatirachi chimasokoneza mfundo ya causality mu zenizeni zozungulira ife. Kapena mwina nthawi ilibe kanthu ikafika pa tinthu tating'onoting'ono? Kuphatikizika kwa Quantum kumaphwanya mfundo yamalo, yomwe imagwira ntchito mufizikiki yachikale, molingana ndi momwe chinthu chimatha kukhudzidwa ndi malo omwe ali pafupi.

Chiyambireni kuyesa kwa Brazil, zoyeserera zambiri zofananira zachitika, zomwe zimatsimikizira kwathunthu zotsatira zomwe zaperekedwa pano. Pamapeto pake, wowerenga akufuna kufotokoza momveka bwino chinsinsi cha zochitika zosayembekezereka izi. Tsoka ilo, izi sizingatheke. Malingaliro a quantum mechanics ndi osiyana ndi malingaliro adziko lapansi omwe timawona tsiku lililonse. Tiyenera kuvomereza izi modzichepetsa ndi kukondwera kuti malamulo a quantum mechanics amalongosola molondola zochitika zomwe zimachitika mu microcosm, zomwe zimagwiritsidwa ntchito bwino pazida zamakono zamakono.