I-Superconductivity isenzakalo esingokomzimba lapho ukumelana kukagesi kwempahla kwehla ku-zero ezingeni lokushisa elithile elibalulekile. Ithiyori ye-Bardeen-Cooper-Schrieffer (BCS) iyincazelo esebenzayo, echaza ukusebenza kahle kwezinto eziningi. Ibonisa ukuthi amapheya e-Cooper electron akhiwe ku-crystal lattice ekushiseni okuphansi ngokwanele, nokuthi i-BCS superconductivity ivela ekuhlanganiseni kwabo. Nakuba i-graphene ngokwayo ingumqhubi kagesi omuhle kakhulu, ayibonisi i-BCS superconductivity ngenxa yokucindezela ukusebenzisana kwe-electron-phonon. Yingakho amakhondaktha amaningi “amahle” (njengegolide nethusi) angama-superconductors “amabi”.
Abacwaningi ku-Center for Theoretical Physics of Complex Systems (PCS) e-Institute of Basic Science (IBS, South Korea) babike enye indlela entsha yokufeza i-superconductivity ku-graphene. Bazuze lokhu ngokuphakamisa uhlelo oluxubile olwakhiwe i-graphene ne-Bose-Einstein condensate (BEC) enezinhlangothi ezimbili. Ucwaningo lushicilelwe kujenali 2D Materials.
Isistimu eyingxube ehlanganisa igesi ye-electron (ungqimba olungaphezulu) ku-graphene, ehlukaniswe ne-condensate ye-Bose-Einstein enezinhlangothi ezimbili, emelwe ama-exciton angaqondile (izendlalelo eziluhlaza okwesibhakabhaka nezibomvu). Ama-electron nama-excitons ku-graphene ahlanganiswe amandla e-Coulomb.
(a) Ukuncika kwezinga lokushisa kwegebe le-superconducting enqubweni ephakathin ene-bukhulun enokulungiswa kwezinga lokushisa (umugqa odayishiwe) nangaphandle kokulungiswa kwezinga lokushisa (umugqa oqinile). (b) Izinga lokushisa elibalulekile loshintsho lwe-superconducting njengomsebenzi wokuminyana kwe-condensate yokusebenzisana okuphakathi nendawo (umugqa onedeshi ebomvu) nangaphandle (umugqa oqinile omnyama) wokulungisa izinga lokushisa. Ulayini onamachashazi aluhlaza ubonisa izinga lokushisa lokushintsha le-BKT njengomsebenzi wokuminyana kwe-condensate.
Ngaphezu kwe-superconductivity, i-BEC ingenye into eyenzekayo emazingeni okushisa aphansi. Yisimo sesihlanu sendaba esabikezelwa okokuqala ngu-Einstein ngo-1924. Ukwakheka kwe-BEC kwenzeka lapho ama-athomu anamandla amancane ehlangana ndawonye futhi angena esimweni esifanayo samandla, okuwumkhakha wocwaningo olubanzi ku-condensed matter physics. Uhlelo lwe-hybrid Bose-Fermi ngokuyisisekelo lumelela ukusebenzisana kongqimba lwama-electron anongqimba lwama-bosons, njengama-excitons angaqondile, ama-exciton-polaron, njalonjalo. Ukusebenzisana phakathi kwezinhlayiya ze-Bose ne-Fermi kuholele ezinhlobonhlobo zamanoveli nezigigaba ezithakazelisayo, ezivuse isithakazelo sazo zombili izinhlangothi. Ukubuka okuyisisekelo nokugxile kuhlelo lokusebenza.
Kulo msebenzi, abacwaningi babike indlela entsha ye-superconducting ku-graphene, okubangelwa ukusebenzisana phakathi kwama-electron kanye "nama-bogolons" kunamaphononi ohlelweni olujwayelekile lwe-BCS. I-Bogolons noma i-Bogoliubov quasiparticles yizinto ezijabulisayo ku-BEC, ezinezici ezithile zezinhlayiya. Ngaphakathi kwezigaba ezithile zepharamitha, lo mshini uvumela izinga lokushisa elibucayi le-superconducting ku-graphene ukuthi lifinyelele phezulu njenge-70 Kelvin. Abacwaningi baphinde basungula ithiyori entsha ye-BCS encane egxile kakhulu ezinhlelweni ezisekelwe ku-graphene entsha eyi-hybrid. Imodeli abayiphakamisile iphinde ibikezele ukuthi izakhiwo ze-superconducting zingakhuphuka ngezinga lokushisa, okuholela ekuncikeni kwezinga lokushisa elingelona le-monotonic legebe le-superconducting.
Ukwengeza, ucwaningo luye lwabonisa ukuthi ukuhlakazwa kwe-Dirac ye-graphene kugcinwa kulolu hlelo oluphakathi. Lokhu kubonisa ukuthi lo mshini we-superconducting uhilela ama-electron ane-relativistic dispersion, futhi lesi simo asizange sihlolwe kahle ku-condensed matter physics.
Lo msebenzi wembula enye indlela yokufeza i-superconductivity ephezulu yokushisa. Ngesikhathi esifanayo, ngokulawula izakhiwo ze-condensate, singakwazi ukulungisa i-superconductivity ye-graphene. Lokhu kubonisa enye indlela yokulawula amadivayisi e-superconducting esikhathini esizayo.
Isikhathi sokuthumela: Jul-16-2021 
