Indaba inemvelo emibili; konke kukhona kokubili njengezinhlayiya namagagasi. Ezingeni lokushisa eliseduze noziro ngokuphelele, imvelo yamaza yama-athomu ibonakala ngemisebe ebangeni elibonakalayo. Kulawa mazinga okushisa abandayo kakhulu ebangeni le-nanoKelvin, ama-athomu ahlangana ebhizinisini elilodwa elikhulu futhi ashintshele esimweni sesihlanu esibizwa nge-Bose Eisenstein Condensate (BEC) esebenza njengegagasi ephaketheni elikhulu. Njengawo wonke amagagasi, ama-athomu akulesi simo abonisa ukwenzeka kokuphazanyiswa futhi amaphethini okuphazanyiswa amagagasi e-athomu angacwaningwa ezindaweni zokucwaninga. Ama-interferometer e-athomu asetshenziswe endaweni ye-microgravity emkhathini asebenza njengenzwa enembe ngokwedlulele futhi anikeze ithuba lokulinganisa ukusheshisa okukhulu okubuthakathaka. Isiqandisi esincane esilingana neCold Atom Laboratory (CAL) ezungeza uMhlaba sigibela i-International Space Station (ISS) iyindawo yocwaningo yocwaningo lwamagesi e-ultra-cold quantum endaweni ye-microgravity yasemkhathini. Yathuthukiswa nge-Atom Interferometer eminyakeni embalwa edlule. Njengombiko oshicilelwe ngomhla ka-13 Agasti 2024), abacwaningi benze ngempumelelo izivivinyo ze-pathfinder. Bangakwazi ukukala ukudlidliza kwe-ISS besebenzisa i-interferometer ene-pulse emithathu ye-Mach–Zehnder esikhungweni se-CAL. Bekungokokuqala ngqa ukuthi kusetshenziswe inzwa ye-quantum emkhathini ukuthola izinguquko endaweni eseduze. Ukuhlolwa kwesibili kuhilele ukusetshenziswa kwe-Ramsey shear-wave interferometry ukuze kubonakale amaphethini okuphazamisa ekugijimeni okukodwa. Amaphethini abonakale ngaphezu kwesikhathi sokunwetshwa samahhala esingu-150 ms. Lona bekuwukubonakaliswa okude kakhulu kwemvelo yamagagasi yama-athomu ekuweni okukhululekile emkhathini. Ithimba locwaningo liphinde lalinganisa i-Bragg laser photon recoil njengokuboniswa kwenzwa ye-quantum yokuqala kusetshenziswa i-athomu interferometry emkhathini. Lezi zenzakalo zibalulekile. Njengezinzwa ezinembe kakhulu, ama-interferometers asekelwe emkhathini we-ultracold athomu angakala ukusheshisa okubuthakathaka kakhulu yingakho enikeza amathuba kubacwaningi ukuhlola imibuzo (njengento emnyama namandla amnyama, i-matter-anti-matter asymmetry, ukuhlanganisa amandla adonsela phansi nezinye izinkambu) ukuthi I-General Relativity kanye ne-Standard Model ye-particle physics ayikwazi ukuchaza futhi ivale igebe ekuqondeni kwethu indawo yonke.
Amagagasi abonisa ukwenzeka kokuphazanyiswa, okungukuthi, amagagasi amabili noma ngaphezulu ahlangene ukuze akhiphe umphumela wamagagasi angase abe nokuphakama okuphezulu noma okuphansi kuye ngezigaba zamagagasi ahlangeneyo. Endabeni yokukhanya, sibona umphumela wamagagasi ngesimo semiphetho emnyama nelula.
I-Interferometry iyindlela yokulinganisa izici kusetshenziswa ukwenzeka kokuphazamiseka. Kufaka phakathi ukuhlukanisa igagasi lesigameko libe yimishayo emibili ehamba izindlela ezihlukene bese ihlangana ukuze yenze iphethini yokuphazamisa noma imiphetho (esimeni sokukhanya). Iphethini yokuphazamisa ewumphumela izwela izinguquko ezimeni zezindlela zokuhamba zemishayo, isibonelo, noma yiluphi ushintsho kubude bendlela yokuhamba noma kunoma iyiphi inkambu ehlobene nobude begagasi buthonya iphethini yokuphazamiseka futhi ingasetshenziselwa izilinganiso.
de Broglie wave noma i-matter wave
Indaba inemvelo emibili; ikhona kokubili njengezinhlayiyana kanye namagagasi. Yonke izinhlayiya ezihambayo noma into inesici segagasi esinikezwe ngu-de Broglie Equation
λ = h/mv = h/p = h/√3mKT
lapho u-λ ingubude begagasi, u-h ewubude obungaguquki, u-m uyisisindo, u-v uyisivinini sezinhlayiya, u-p umfutho, u-K ungowe-Boltzmann, kanti u-T izinga lokushisa ku-Kelvin.
I-thermal de Broglie wavelength ilingana ngokuphambene nempande eyisikwele yezinga lokushisa nge-kelvin okusho ukuthi λ izoba nkulu kuzinga lokushisa eliphansi.
Ucwaningo lwamagagasi e-athomu abandayo kakhulu
Ku-athomu evamile, ubude beza beza be-Broglie kuzinga lokushisa legumbi bulandelana nge-angstrom (10-10 m) okungukuthi. 0.1 nanometer (1 nm=10-9 m). Imisebe yobude obunikeziwe ingaxazulula imininingwane ebangeni losayizi ofanayo. Ukukhanya akukwazi ukuxazulula imininingwane emincane kunobude bayo beza ngakho-ke i-athomu evamile ekamelweni lokushisa alikwazi ukuthathwa isithombe kusetshenziswa ukukhanya okubonakalayo okunobude begagasi kububanzi obungaba ngu-400 nm kuya ku-700 nm. Ama-X ray angakwenza ngenxa yobude bayo bebanga be-angstrom kodwa amandla ayo aphezulu abhubhisa wona kanye ama-athomu okufanele awabuke. Ngakho-ke, isixazululo silele ekunciphiseni izinga lokushisa le-athomu (liye ngaphansi kuka-10-6 kelvin) ukuze amaza kade e-Broglie ama-athomu ande futhi aqhathaniswe namaza okukhanya okubonakalayo. Emazingeni okushisa ama-ultracold, imvelo yamagagasi yama-athomu iyalinganiseka futhi ifaneleke ku-interferometry.
Njengoba izinga lokushisa lama-athomu liyehla ngokuqhubekayo ebangeni le-nanokelvin (10-9 kelvin) ibanga ukuya ku-400 nK, i-atomic bosons ishintshela esimweni sesihlanu esibizwa nge-Bose-Einstein condensate (BCE). Kulawa mazinga okushisa aphansi kakhulu eduze kweziro ngokuphelele lapho ukunyakaza okushisayo kwezinhlayiya kuba yinto encane kakhulu, ama-athomu ahlangana abe into eyodwa enkulu esebenza njengegagasi ephaketheni elikhulu. Lesi simo sama-athomu sinikeza ithuba kubacwaningi ukuthi bafunde izinhlelo ze-quantum esikalini se-macroscopic. I-athomu yokuqala BCE yadalwa ngo-1995 ngegesi ye-athomu ye-rubidium. Kusukela lapho, le ndawo ibone ukuthuthuka okuningi kwezobuchwepheshe. I i-molecular BEC yama-molecule e-NaCs asanda kwakhiwa ezingeni lokushisa elibandayo elingu-5 nanoKelvin (nK).
Izimo ze-Microgravity emkhathini zingcono ocwaningweni lwemishini ye-quantum
Amandla adonsela phansi ezindaweni zokucwaninga asekelwe emhlabeni adinga ukusetshenziswa kwesicupho kazibuthe ukuze kubambe ama-athomu endaweni yokupholisa ngempumelelo. Amandla adonsela phansi futhi akhawulela isikhathi sokusebenzisana nama-BEC kumalabhorethri asemhlabeni. Ukwakhiwa kwama-BEC endaweni ye-microgravity yamalabhorethri asemkhathini kuyayinqoba le mikhawulo. Imvelo ye-Microgravity ingandisa isikhathi sokusebenzisana futhi inciphise ukuphazamiseka okuvela endaweni esetshenzisiwe, ngaleyo ndlela isekele kangcono ucwaningo lwemishini ye-quantum. Ama-BCE manje akhiwa njalo ngaphansi kwezimo ze-microgravity emkhathini.
I-Cold Atom Laboratory (CAL) e-International Space Station (ISS)
I-Cold Atom Laboratory (CAL) iyisikhungo sokucwaninga esinabasebenzisi abaningi esizinze e-International Space Station (ISS) ukuze kucwaningwe amagesi e-quantum abandayo kakhulu endaweni ye-microgravity yasemkhathini. I-CAL isetshenziswa ukude nesikhungo sokusebenza eJet Propulsion Laboratory.
Kulesi sikhungo esisekelwe emkhathini, kungenzeka ukuthi ube nezikhathi zokubuka ngaphezu kwemizuzwana eyi-10 kanye nezinga lokushisa elibandayo elingaphansi kuka-100 picoKelvin (1 pK= 10-12 Kelvin) ocwaningweni lwe-quantum phenomena.
I-Cold Atom Lab yethulwa mhla zingama-21 kuNhlaba wezi-2018 futhi yafakwa ku-ISS ekupheleni kukaMeyi 2018. I-Bose-Einstein Condensate (BEC) yakhiwe kulesi sikhungo esisekelwe emkhathini ngoJulayi 2018. Lokhu bekungokokuqala; isimo sesihlanu sezinto sadalwa emzileni womhlaba. Kamuva, lesi sikhungo sathuthukiswa kulandela ukuthunyelwa kwama-interferometers e-athomu e-ultracold.
I-CAL ifinyelele iziqophamlando eziningi eminyakeni yamuva. I-Rubidium Bose–Einstein condensates (BECs) yakhiqizwa emkhathini ngo-2020. Kwaboniswa futhi ukuthi indawo ye-microgravity inenzuzo ekuhloleni kwe-athomu ebandayo.
Ngonyaka odlule, ngo-2023, abacwaningi bakhiqiza izinhlobo ezimbili ze-BEC ezakhiwe ngazo 87Rb kanye 41K futhi yabonisa i-interferometry ye-athomu kanyekanye enezinhlobo ezimbili ze-athomu okokuqala ngqa emkhathini endaweni ye-Cold Atom Laboratory. Lezi zimpumelelo bezibalulekile ezivivinyweni ze-quantum ze-universality of free fall (UFF) emkhathini.
Intuthuko yakamuva kubuchwepheshe be-quantum obusekelwe emkhathini
Ngokombiko oshicilelwe ngomhla ka-13 Agasti 2024), abacwaningi baqashwe 87Ama-athomu e-Rb ku-interferometer ye-athomu ye-CAL futhi enze ngempumelelo izivivinyo ezintathu zokuthola indlela. Bangakwazi ukukala ukudlidliza kwe-ISS besebenzisa i-interferometer ene-pulse emithathu ye-Mach–Zehnder esikhungweni se-CAL. Bekungokokuqala ngqa ukuthi kusetshenziswe inzwa ye-quantum emkhathini ukuthola izinguquko endaweni eseduze. Ukuhlolwa kwesibili kuhilele ukusetshenziswa kwe-Ramsey shear-wave interferometry ukuze kubonakale amaphethini okuphazamisa ekugijimeni okukodwa. Amaphethini abonakale ngaphezu kwesikhathi sokunwetshwa samahhala esingu-150 ms. Lona bekuwukubonakaliswa okude kakhulu kwemvelo yamagagasi yama-athomu ekuweni okukhululekile emkhathini. Ithimba locwaningo liphinde lalinganisa i-Bragg laser photon recoil njengokuboniswa kwenzwa ye-quantum yokuqala kusetshenziswa i-athomu interferometry emkhathini.
Ukubaluleka kwama-interferometer e-athomu e-ultracold afakwe emkhathini
Ama-interferometer e-athomu asebenzisa i-quantum yemvelo yama-athomu futhi azwela kakhulu ezinguqukweni zokusheshisa noma ezinkambu ngakho-ke anezinhlelo zokusebenza njengamathuluzi anemba okuphezulu. Ama-interferometer asekelwe eMhlabeni asetshenziselwa ukutadisha amandla adonsela phansi kanye nobuchwepheshe bokuzulazula obuphambili.
Ama-interferometer asuselwa emkhathini ane-athomu enezinzuzo zemvelo eqhubekayo ye-microgravity enikeza izimo zokuwa zamahhala ezinethonya elincane kakhulu lezinkambu. Iphinde isize i-Bose-Einstein condensates (BECs) ifinyelele amazinga okushisa abandayo ebangeni le-picoKelvin futhi ibe khona isikhathi eside. Umthelela ophelele wukunwetshwa kwesikhathi sokubuka yingakho kube nethuba elingcono lokufunda. Lokhu kunikeza ama-interferometer e-athomu e-ultracold afakwe emkhathini ngamakhono okulinganisa okunemba okuphezulu futhi awenze izinzwa ezinkulu.
Ama-interferometer e-athomu e-Ultracold asetshenziswe emkhathini angathola ukuhlukahluka okucashile kwamandla adonsela phansi okuyinkomba yokuhlukahluka kokuminyana. Lokhu kungasiza ekutadisheni ukwakheka kwemizimba yamaplanethi nanoma yiziphi izinguquko ezinkulu.
Ukulinganisa okunembe okuphezulu kwamandla adonsela phansi kungasiza futhi ukuqonda kangcono izinto ezimnyama namandla amnyama kanye nasekuhloleni amandla acashile angaphezu kweGeneral Relativity kanye Nemodeli Ejwayelekile echaza indawo yonke ebonakalayo.
I-General Relativity kanye ne-Standard Model yimibono emibili echaza indawo yonke ebonakalayo. Imodeli evamile ye-particle physics ngokuyisisekelo ithiyori ye-quantum field. Ichaza kuphela i-5 % yendawo yonke, enye i-95% isesimweni esimnyama (indaba emnyama namandla amnyama) esingaziqondi. Imodeli Ejwayelekile ayikwazi ukuchaza izinto ezimnyama namandla amnyama. Ayikwazi ukuchaza i-asymmetry ye-matter-antimatter futhi. Ngokufanayo, amandla adonsela phansi awakwazanga ukuhlanganiswa nezinye izinkambu okwamanje. Iqiniso lendawo yonke alichazwa ngokugcwele ngamathiyori namamodeli amanje. Ama-accelerator amakhulu nama-observatories awakwazi ukukhanyisa okuningi kwalezi zimfihlakalo zemvelo. Njengezinzwa ezinembe kakhulu, ama-interferometer asekelwe emkhathini we-ultracold athomu anikeza amathuba kubacwaningi ukuthi bahlole le mibuzo ukuze bavale igebe ekuqondeni kwethu indawo yonke.
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References:
- Meystre, Pierre 1997. Lapho ama-athomu eba amagagasi. Itholakala ngo https://wp.optics.arizona.edu/pmeystre/wp-content/uploads/sites/34/2016/03/when-atoms.pdf
- NASA. Cold Atom Laboratory - Universe Missions. Itholakala ngo https://www.jpl.nasa.gov/missions/cold-atom-laboratory-cal & https://coldatomlab.jpl.nasa.gov/
- Aveline, DC, et al. I-Observation of Bose-Einstein ihlanganisa elebhu yocwaningo ezungeza umhlaba. Imvelo 582, 193–197 (2020). https://doi.org/10.1038/s41586-020-2346-1
- Elliott, ER, Aveline, DC, Bigelow, NP et al. Izingxube zegesi ye-quantum kanye ne-interferometry yezinhlobo ezimbili ze-athomu emkhathini. Imvelo 623, 502–508 (2023). https://doi.org/10.1038/s41586-023-06645-w
- Williams, JR, et al 2024. I-Pathfinder ihlola nge-athomu interferometry ku-Cold Atom Lab egibele i-International Space Station. I-Nat Commun 15, 6414. Kushicilelwe: 13 Agasti 2024. DOI: https://doi.org/10.1038/s41467-024-50585-6 . Inguqulo yokuphrinta https://arxiv.org/html/2402.14685v1
- I-NASA Ibonisa Inzwa Ye-Quantum 'Yokuphola Kakhulu' Okokuqala Emkhathini. Ishicilelwe ngomhla ka-13 Agasti 2024.Iyatholakala e- https://www.jpl.nasa.gov/news/nasa-demonstrates-ultra-cool-quantum-sensor-for-first-time-in-space
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