Matter yana da yanayi biyu; komai ya wanzu duka a matsayin barbashi da igiyar ruwa. A yanayin zafi kusa da cikakken sifili, yanayin raƙuman atom ɗin zai zama abin gani ta hanyar radiation a cikin kewayon bayyane. A irin wannan yanayin zafi mai zafi a cikin kewayon nanoKelvin, ƙwayoyin zarra suna haɗuwa zuwa cikin babban mahalli guda ɗaya kuma suna canzawa zuwa jiha ta biyar da ake kira Bose Eisenstein Condensate (BEC) wanda ke zama kamar igiyar ruwa a cikin babban fakiti. Kamar kowane raƙuman ruwa, ƙwayoyin zarra a cikin wannan jihar suna nuna yanayin tsangwama kuma ana iya nazarin tsarin tsangwama na igiyoyin atom a cikin dakunan gwaje-gwaje. Atom interferometers da aka tura a cikin yanayin microgravity na sararin samaniya suna aiki azaman firikwensin daidaitaccen firikwensin kuma yana ba da dama don auna mafi ƙarancin hanzari. Karamin firij mai girman Cold Atom Laboratory (CAL) da ke kewaya duniya a tashar sararin samaniya ta kasa da kasa (ISS) wani wurin bincike ne don nazarin iskar gas mai tsananin sanyi a cikin yanayin microgravity na sararin samaniya. An inganta shi tare da Atom Interferometer ƴan shekaru da suka wuce. Kamar yadda rahoton da aka buga a ranar 13 ga Agusta 2024), masu bincike sun yi nasarar gudanar da gwaje-gwajen gano hanya. Za su iya auna rawar jiki na ISS ta amfani da ma'aunin bugun jini na Mach-Zehnder a kan cibiyar CAL. Wannan shine karo na farko da aka yi amfani da na'urar firikwensin kididdigar a sararin samaniya don gano canje-canje a kewayen nan take. Gwaji na biyu ya ƙunshi amfani da interferometry na Ramsey shear-wave interferometry don bayyana tsarin tsangwama a cikin gudu ɗaya. An lura da tsarin sama da 150 ms lokacin faɗaɗa kyauta. Wannan shine mafi tsayin nunin yanayin raƙuman atom a cikin faɗuwar sararin samaniya. Ƙungiyar binciken ta kuma auna recoil na Bragg Laser photon recoil a matsayin nunin firikwensin kididdigar farko ta amfani da interferometry a cikin sararin samaniya. Waɗannan ci gaban suna da mahimmanci. A matsayin mafi daidaitattun na'urori masu auna firikwensin, na'urorin atom na tushen sararin samaniya na iya auna saurin haɓaka mai rauni don haka suna ba da dama ga masu bincike don bincika tambayoyin (kamar al'amuran duhu da makamashi mai duhu, asymmetry-anti-matter asymmetry, haɗa nauyi tare da sauran fannoni) cewa Babban Dangantaka da Madaidaicin Samfurin ilimin kimiyyar barbashi ba za su iya yin bayani da cike gibin fahimtarmu game da sararin samaniya ba.
Raƙuman ruwa suna nuna yanayin tsangwama, watau, raƙuman ruwa biyu ko fiye suna haɗuwa don haifar da raƙuman ruwa wanda zai iya samun girman girma ko ƙasa da girma dangane da matakan haɗa taguwar ruwa. A cikin yanayin haske, muna ganin raƙuman raƙuman ruwa a cikin nau'i na duhu da haske.
Interferometry hanya ce ta auna halaye ta amfani da abin da ke faruwa na tsoma baki. Ya ƙunshi raba igiyar abin da ya faru zuwa katako guda biyu waɗanda ke tafiya ta hanyoyi daban-daban sannan su haɗu don samar da sakamakon tsangwama ko gefuna (a yanayin haske). Sakamakon tsangwama yana kula da canje-canje a yanayin hanyoyin tafiye-tafiye na katako, alal misali, duk wani canji na tsawon hanyar tafiya ko a kowane fanni dangane da tsayin igiyar igiyar ruwa yana rinjayar tsarin tsangwama kuma ana iya amfani dashi don aunawa.
de Broglie wave ko kwayoyin kalaman
Matter yana da yanayi biyu; ya wanzu duka a matsayin barbashi da kalaman. Kowane barbashi ko abu mai motsi yana da sifa ta raƙuman ruwa wanda de Broglie Equation ya bayar
λ = h/mv = h/p = h/√3mKT
inda λ yake da tsayi, h shine madaidaicin Planck, m shine taro, v shine saurin barbashi, p shine ƙarfin lokaci, K shine Boltzmann akai-akai, kuma T shine zafin jiki a Kelvin.
Thermal de Broglie wavelength ya saba daidai da murabba'in tushen zafin jiki a kelvin ma'ana λ zai fi girma a ƙananan zafin jiki.
Nazarin raƙuman zarra mai sanyi
Ga zarra na yau da kullun, tsayin raƙuman ruwan de Broglie a yanayin zafin ɗaki yana cikin tsari na angstrom (10).-10 m) wato. 0.1 nanometer (1 nm=10-9 m). Radiyo na tsawon zangon da aka bayar zai iya warware cikakkun bayanai a cikin girman girman girman. Haske ba zai iya warware cikakkun bayanai ƙasa da tsayinsa ba don haka ba za a iya siffanta zarra na al'ada a cikin ɗaki ta amfani da hasken bayyane wanda ke da tsayin daka a cikin kewayon kusan nm 400 zuwa 700 nm. Hoton X-ray na iya yin shi saboda tsawon zangonsa na angstrom amma yawan kuzarinsa yana lalata kwayoyin halittar da ya kamata a lura dasu. Don haka, maganin yana cikin rage zafin zarra (zuwa ƙasa da 10-6 kelvin) ta yadda de Broglie wavelengths na atom ɗin ya ƙaru kuma ya zama kwatankwacin tsayin raƙuman haske na bayyane. A yanayin zafi na ultracold, yanayin motsin atom ɗin ya zama abin aunawa kuma yana dacewa da interferometry.
Kamar yadda zafin atom ɗin ya ƙara raguwa a cikin kewayon nanokelvin (10-9 kelvin) ya kai kusan 400 nK, atomic bosons yana canzawa zuwa al'amuran jiha ta biyar da ake kira Bose-Einstein condensate (BCE). A irin wannan matsananci-ƙananan yanayin zafi kusa da cikakkiyar sifili lokacin da motsin thermal na ɓangarorin ya zama mara kyau sosai, ƙwayoyin zarra suna haɗawa zuwa babban mahalli guda ɗaya wanda ke aiki azaman igiyar ruwa a cikin babban fakiti. Wannan yanayin atom yana ba da dama ga masu bincike don nazarin tsarin ƙididdiga akan ma'aunin ma'auni. An kirkiro atomic na farko BCE a cikin 1995 a cikin iskar rubidium atom. Tun daga wannan lokacin, wannan yanki ya ga ci gaban fasaha da yawa. The kwayoyin BEC Kwanan nan an ƙirƙiri ƙwayoyin ƙwayoyin NaCs a zafin jiki na 5 nanoKelvin (nK).
Yanayin microgravity a sararin samaniya ya fi kyau don bincike na inji mai ƙididdigewa
Girman nauyi a cikin dakunan gwaje-gwajen da ke ƙasa yana buƙatar amfani da tarkon maganadisu don riƙe atom ɗin a wurin don ingantaccen sanyaya. Hakanan nauyi yana iyakance lokacin hulɗa tare da BECs a cikin dakunan gwaje-gwaje na ƙasa. Samar da BECs a cikin mahallin microgravity na dakunan gwaje-gwaje na tushen sararin samaniya ya shawo kan waɗannan iyakoki. Yanayin microgravity na iya ƙara lokacin hulɗa tare da rage damuwa daga filin da aka yi amfani da shi, don haka mafi kyawun tallafawa bincike na inji. BCEs yanzu ana yin su akai-akai a ƙarƙashin yanayin microgravity a sararin samaniya.
Cold Atom Laboratory (CAL) a Tashar Sararin Samaniya ta Duniya (ISS)
Cold Atom Laboratory (CAL) cibiyar bincike ce ta masu amfani da yawa da aka kafa a tashar sararin samaniya ta kasa da kasa (ISS) don nazarin iskar gas mai tsananin sanyi a cikin yanayin microgravity na sararin samaniya. Ana sarrafa CAL daga nesa daga cibiyar aiki a dakin gwaje-gwaje na Jet Propulsion.
A wannan wurin tushen sararin samaniya, yana yiwuwa a sami lokutan kallo sama da daƙiƙa 10 da yanayin zafi mai zafi ƙasa da 100 picoKelvin (1 pK= 10).-12 Kelvin) don nazarin abubuwan mamaki.
An ƙaddamar da Cold Atom Lab a ranar 21 ga Mayu 2018 kuma an shigar da shi akan ISS a ƙarshen Mayu 2018. An ƙirƙiri Bose-Einstein Condensate (BEC) a cikin wannan wurin da ke sararin samaniya a cikin Yuli 2018. Wannan shi ne karo na farko; An halicci yanayi na biyar a cikin kewayar duniya. Daga baya, an inganta wurin bayan tura na'urorin atom na ultracold.
CAL ya sami nasarori da yawa a cikin 'yan shekarun nan. Rubidium Bose-Einstein condensates (BECs) an samar dashi a sararin samaniya a cikin 2020. An kuma nuna cewa yanayin microgravity yana da fa'ida don gwajin sanyi-atom.
A bara, a cikin 2023, masu bincike sun samar da nau'ikan nau'ikan BEC guda biyu waɗanda aka kirkira daga 87Rb da 41K da kuma nuna interferometry na lokaci guda tare da nau'in atomic guda biyu a karon farko a cikin sararin samaniya a cikin kayan aikin Cold Atom Laboratory. Waɗannan nasarorin sun kasance masu mahimmanci don gwajin ƙididdigewa na faɗuwar kyauta (UFF) a sararin samaniya.
Ci gaban kwanan nan a cikin fasahar ƙididdiga ta tushen sarari
Kamar yadda rahoton da aka buga a kan 13 Agusta 2024), masu bincike sun yi aiki 87Rb atom a cikin CAL atom interferometer kuma yayi nasarar gudanar da gwaje-gwajen gano hanya guda uku. Za su iya auna rawar jiki na ISS ta amfani da ma'aunin bugun jini na Mach-Zehnder a kan cibiyar CAL. Wannan shine karo na farko da aka yi amfani da na'urar firikwensin kididdigar a sararin samaniya don gano canje-canje a kewayen nan take. Gwaji na biyu ya haɗa da amfani da interferometry na Ramsey shear-wave interferometry don bayyana tsarin tsangwama a cikin gudu guda. An lura da tsarin sama da 150 ms lokacin faɗaɗa kyauta. Wannan shine mafi tsayin nunin yanayin raƙuman atom a cikin faɗuwar sararin samaniya. Ƙungiyar binciken kuma ta auna recoil na Bragg Laser photon recoil a matsayin nunin firikwensin kididdigar farko ta amfani da interferometry a cikin sararin samaniya.
Muhimmancin ultracold atom interferometers da aka tura zuwa sararin samaniya
Atom interferometers suna amfani da nau'in nau'in kwayoyin halitta kuma suna da matukar damuwa ga canje-canje a hanzari ko filayen don haka suna da aikace-aikace a matsayin ainihin kayan aikin. Ana amfani da interferometers na tushen duniya don nazarin nauyi da kuma cikin fasahar kewayawa na ci gaba.
Interferometers na tushen sararin samaniya suna da fa'idodi na yanayin microgravity mai dorewa wanda ke ba da yanayin faɗuwa kyauta tare da ƙarancin tasirin filayen. Hakanan yana taimakawa condensates Bose-Einstein (BECs) su isa yanayin sanyi a cikin kewayon picoKelvin kuma suna wanzu na tsawon lokaci. Tasirin yanar gizon yana ƙara lokacin kallo don haka mafi kyawun damar yin karatu. Wannan yana ba da ultracold atom interferometers da aka tura zuwa sararin samaniya tare da madaidaicin ma'auni kuma ya mai da su manyan firikwensin.
Ultracold atom interferometers da aka tura a sararin samaniya na iya gano bambance-bambancen da hankali a cikin nauyi wanda ke nuni da bambancin yawa. Wannan zai iya taimakawa wajen nazarin abubuwan da ke tattare da jikin taurari da kowane canje-canjen taro.
Madaidaicin ma'aunin nauyi na iya taimakawa mafi kyawun fahimtar al'amuran duhu da kuzari mai duhu da kuma binciken dabaru masu ƙarfi fiye da Gabaɗaya Dangantaka da Misalin Ma'auni wanda ke bayyana sararin samaniya.
Gabaɗaya Dangantaka da Madaidaicin Samfurin su ne ka'idoji guda biyu waɗanda ke bayyana sararin da ake gani. Daidaitaccen samfurin ilimin kimiyyar lissafi shine ainihin ka'idar filin kida. Ya bayyana kashi 5 cikin 95 na sararin samaniya, sauran kashi XNUMX% na cikin sifofi masu duhu (dark matter da duhun kuzari) da ba mu gane ba. Madaidaicin Model ba zai iya yin bayanin duhun kwayoyin halitta da duhun kuzari ba. Ba zai iya yin bayanin asymmetry na kwayoyin halitta-antimatter ba. Hakazalika, ba a iya haɗa nauyi da sauran filayen tukuna. Haƙiƙanin sararin samaniya ba a cika yin cikakken bayani game da ka'idodi da ƙira na yanzu ba. Manyan masu hanzari da masu lura ba su iya ba da haske a kan yawancin waɗannan asirai na yanayi. A matsayin ingantattun na'urori masu auna firikwensin, na'urorin atom na ultracold atom interferometers suna ba da dama ga masu bincike don bincika waɗannan tambayoyin don cike gibin fahimtarmu game da sararin samaniya.
***
References:
- Meystre, Pierre 1997. Lokacin da kwayoyin halitta suka zama taguwar ruwa. Akwai a https://wp.optics.arizona.edu/pmeystre/wp-content/uploads/sites/34/2016/03/when-atoms.pdf
- NASA. Cold Atom Laboratory - Ayyukan Duniya. Akwai a https://www.jpl.nasa.gov/missions/cold-atom-laboratory-cal & https://coldatomlab.jpl.nasa.gov/
- Aveline, DC, da dai sauransu. Dubawa na Bose-Einstein condensates a cikin dakin bincike mai kewaya duniya. Yanayin 582, 193-197 (2020). https://doi.org/10.1038/s41586-020-2346-1
- Elliott, ER, Aveline, DC, Bigelow, NP et al. Haɗin iskar gas mai ƙididdigewa da nau'ikan nau'ikan atom interferometry a sararin samaniya. Yanayin 623, 502-508 (2023). https://doi.org/10.1038/s41586-023-06645-w
- Williams, JR, et al 2024. Gwaje-gwajen Pathfinder tare da atom interferometry a cikin Cold Atom Lab a kan tashar sararin samaniya ta kasa da kasa. Nat Commun 15, 6414. An buga: 13 Agusta 2024. DOI: https://doi.org/10.1038/s41467-024-50585-6 . Sigar bugu https://arxiv.org/html/2402.14685v1
- NASA Ta Nuna Ƙaƙƙarfan Sensor na 'Ultra-Cool' a karon farko a sararin samaniya. An buga 13 Agusta 2024. Akwai a https://www.jpl.nasa.gov/news/nasa-demonstrates-ultra-cool-quantum-sensor-for-first-time-in-space
***
