ION ƊAYA NA RUWA A LOKACI ƊAYA: HYDROGEN TA DOKE DEUTERIUM A CIKIN SANYI

Tsakanin taurari, a cikin gizagizai inda zafin jiki zai iya sauka zuwa ’yan kelvin — ’yan digiri sama da cikakken sanyi (absolute zero) — ilmin sinadarai yana tafiya ne galibi kan martani tsakanin molecules masu caji da marasa caji, waɗanda sau da yawa ba sa buƙatar kuzari kafin su fara. Wani muhimmin ɗan wasa shi ne cation na ruwa (molecule na ruwa mai cajin positive), H₂O⁺, wani matsakaicin mataki a kan hanyar samuwar ruwa a cikin iskar gas na tsakanin taurari. Idan ya haɗu da HD — molecule na hydrogen wanda ɗaya daga cikin atom ɗinsa deuterium ne, nau’in hydrogen mai nauyi — zai iya sace kowanne daga cikin atom ɗin biyu:

• ya ɗauki H ya zama H₃O⁺, ya saki D;
• ya ɗauki D ya zama H₂DO⁺, ya saki H.

Hanyar da martanin ya bi tana tsara yadda ake rarraba deuterium tsakanin molecules a sararin samaniya, wato “fractionation” ɗinsa. Gwaje-gwajen baya sun nuna cewa wannan daidaito ya dogara sosai kan kuzarin karo — don haka kan zafin wurin.

Ɗakunan gwaji sun tsaya a kelvin 350

Ma’aunan baya sun rufe kuzarin karo daga 0.03 zuwa 10 electronvolt. Mafi ƙanƙanta, 0.03 eV, shi ne kuzarin karo na yau da kullum a cikin iskar gas mai kusan kelvin 350: zafi ya ninka da girman kima (orders of magnitude) da dama fiye da na gizagizan molecules masu sanyi. Marubutan sun ce ƙiyasta ƙima zuwa ƙasa (extrapolation) yana da haɗari: a cikin sanyi, tasirin quantum kamar tunnelling na iya zama mai yanke hukunci. Adadin ƙananan zafi kaɗai da suka sani, 57% da 43% don fifita H₃O⁺, ya fito ne daga tarko da zai iya kaiwa kelvin 13, amma ba a taɓa bayar da ainihin zafin wannan ma’auni ba.

Ion ɗaya, abokin karo ɗaya

Nanditha Sunil Kumar, Prerna Paliwal, Stefan Willitsch da abokan aikinsu a University of Basel, tare da Anyang Li na Northwest University a Xi’an (China), Hua Guo na University of New Mexico (Amurka) da wasu, sun gina hanyar kallon martanin molecule ɗaya a lokaci ɗaya.

Tarkon ion ɗinsu na radiofrequency yana a kelvin 5.4, a cikin garkuwoyi biyu masu sanyi na kariya daga radiation, a cikin wuri mara iska (vacuum) na kusan 4 × 10⁻¹⁴ millibar. Kowane zagaye yana farawa da ’yan gomomi na ion na calcium, waɗanda laser ke sanyayawa har sai sun daskare cikin tsari mai kyau da ake kira Coulomb crystal. Sai bugun laser ya mayar da molecule ɗaya daga cikin layin tururin ruwa zuwa ion guda na H₂O⁺ a cikin crystal ɗin. Ion na calcium suna haskakawa a ƙarƙashin laser; ion na ruwa ba ya haskakawa, don haka yana bayyana a matsayin ɗigo mai duhu. Kawai ta hanyar mu’amala da ion na calcium masu sanyi, yana sanyaya zuwa ’yan kashi dubu na kelvin. Sai ƙungiyar ta kori ion na calcium har sai ma’aurata kawai suka rage: calcium ɗaya, ion na ruwa ɗaya.

Tsarin gwajin (hagu), crystal na calcium da aka rage zuwa ion ɗaya na calcium da ion na ruwa mai duhu (tsakiya), da lokacin martani: ion na calcium ya daina girgiza (dama). — Figure 1, Sunil Kumar et al. (2026), arXiv:2610.32904.

Ana sakin iskar HD, mai tsafta kusan 97%, a hankali. Kafin ta kai ga ion ɗin, molecules ɗinta suna bugewa kuma suna manne wa bangon masu sanyi sau da yawa, har sai sun natsu a kelvin 5.4 na bangon. Kuzarin karo yana fitowa kusan gaba ɗaya daga motsin molecules na HD kansu, ion ɗin ba ya ƙara komai sai kaɗan: a matsakaici millielectronvolt 0.6 (electronvolt ma’aunin kuzari ne ga ƙwayoyi guda-guda), wanda ya yi daidai da kusan kelvin 7 a kan ma’auni ɗaya da kelvin 350 da ke sama.

Auna abin da aka samar ba tare da taɓa shi ba

Ta yaya za a gane wane abu ne ya samu? Ta nauyinsa. Ma’auratan ion suna girgiza a tsawon tarkon a wani mita (frequency) da ya dogara da nauyin ion mai duhu: kilohertz 531.9 tare da H₂O⁺, 529.2 tare da H₃O⁺, 526.4 tare da H₂DO⁺. Ƙungiyar tana girgiza ma’auratan a 531.9 kHz; hoton ion na calcium yana dushewa. Lokacin da ion na ruwa ya yi martani, nauyinsa yana canzawa, girgizar ta daina aiki kuma hoton ya fito fili. Gwada sauran mitoci biyu yana bayyana abin da aka samar.

Martani yawanci yana zuwa bayan kusan daƙiƙa 100. Ragowar hydrogen a cikin vacuum ɗin ma za ta iya mayar da ion ɗin zuwa H₃O⁺, amma sai bayan kusan awanni 4.5 a matsakaici, don haka da ƙyar take shafar ƙidayar.

271 zuwa 170

A cikin kwanaki 16, ƙungiyar ta naɗa martani 441: H₃O⁺ 271 da H₂DO⁺ 170. Saboda kusan 3% na iskar gas ɗin hydrogen ce ta yau da kullum, H₂, wadda za ta iya ba da H₃O⁺ kawai, sun cire kasonta da ake tsammani. Sakamakon: rabo na 1.50 ± 0.15, wato kusan 60% H₃O⁺ da 40% H₂DO⁺. Mika hydrogen yana yin nasara a cikin sanyi, kamar yadda aka gani a kuzari mafi girma, ko da yake ba da ƙarfi kamar a wasu daga cikinsu ba.

Hagu, abubuwan da aka samar da aka ƙirga a kowace rana daga cikin kwanaki 16 da rabon kowace rana. Dama, rabon idan aka kwatanta da kuzarin karo: sabon ma’auni (murabba’i shuɗi) yana a kuzari mafi ƙanƙanta nesa ba kusa ba da gwaje-gwajen baya (toka) kuma kusa da sababbin kwaikwayo (alwatika ja). — Figure 2, Sunil Kumar et al. (2026), arXiv:2610.32904.

An kama a cikin rami

Don fassara sakamakon, ƙungiyar ta gudanar da kwaikwayon kwamfuta na karon: karo 20,000 da aka kwaikwaya (trajectories) a kowane kuzarin karo, daga millielectronvolt 0.9 zuwa electronvolt 0.9. Rabon da aka yi hasashe yana ƙaruwa tare da kuzari, ya kai ƙoli kusan millielectronvolt 40 zuwa 80, sannan ya faɗi.

Hanyoyi biyu suna gasa. A kuzari mai yawa, martanin kai tsaye ne: ana ƙwace atom ɗin a wucewa ɗaya mai sauri, ba tare da abokan karon sun daɗe tare ba. A ƙaramin kuzari, yawancin karo suna makalewa na ɗan lokaci a cikin wani rami na taswirar kuzari (energy landscape) — jan hankalin juna yana riƙe su tare, kamar ƙwallon marmara a cikin rami — kafin su yi martani. A can, kuzarin bugun yana yaɗuwa cikin girgizar haɗakar wucin gadi (complex), kuma fifikon hydrogen yana dusashewa. Gwargwadon tsawon rayuwar haɗakar, gwargwadon raunin fifikon: a cikin kwaikwayon a kusan kelvin 10, cikin karon da suka makale, rabon yana sauka daga 1.35 ga zama mafiya gajarta zuwa 1.21 ga mafiya tsawo.

Giɓin da aka bari a buɗe

Kwaikwayon suna ba da 1.15 a millielectronvolt 0.9 (kusan kelvin 10); gwajin yana ba da 1.50. Marubutan suna kiran wannan daidaituwa ta fuskar inganci (qualitative). Giɓin zai iya fitowa daga tasirin quantum da kwaikwayon suka bari, kamar tunnelling na hydrogen, ko daga kurakurai a cikin taswirar kuzarin da aka lissafa. Kuma zai iya fitowa daga iskar gas ɗin kanta: ƙasa da kusan kelvin 10, H₂ da HD na iya manne wa bangon da gawayin da aka kunna (activated charcoal), wanda ake amfani da shi don zuƙe ragowar iskar gas, ta hanyoyi daban-daban; ba a san halin wannan gawayi a waɗannan yanayin zafi ba. Idan H₂ da ta kai ga ion ɗin ta fi 3% da aka ɗauka, in ji marubutan, rabon 1.50 da aka auna zai iya zama ya wuce ainihin ƙima (overestimate).