I-Superconductivity yinto ebonakalayo apho ukumelana nombane kwezinto kuyehla kuye ku-zero kubushushu obuthile obubalulekileyo. Ithiyori yeBardeen-Cooper-Schrieffer (BCS) yinkcazo esebenzayo, echaza i-superconductivity kwizinto ezininzi. Ibonisa ukuba ii-Cooper electron pairs zenziwa kwi-crystal lattice kubushushu obuphantsi ngokwaneleyo, kwaye i-BCS superconductivity ivela ekujikeni kwazo. Nangona i-graphene ngokwayo ingumqhubi wombane obalaseleyo, ayibonisi i-BCS superconductivity ngenxa yokuthintelwa kokunxibelelana kwe-electron-phonon. Yingakho uninzi lwabaqhubi "abalungileyo" (njengegolide kunye nobhedu) bengababaqhubi "ababi".
Abaphandi kwiZiko leFiziksi yeTheoretical of Complex Systems (PCS) kwi-Institute of Basic Science (IBS, eMzantsi Korea) baxele ngendlela entsha eyahlukileyo yokufezekisa i-superconductivity kwi-graphene. Bafezekise le mpumelelo ngokucebisa inkqubo exutyiweyo eyenziwe yi-graphene kunye ne-Bose-Einstein condensate (BEC) enemilinganiselo emibini. Olu phando lupapashwe kwijenali i-2D Materials.
Inkqubo ye-hybrid equlathe igesi ye-electron (umaleko ophezulu) kwi-graphene, eyahlulwe kwi-Bose-Einstein condensate enemilinganiselo emibini, emelwe zii-excitons ezingathanga ngqo (umaleko oluhlaza okwesibhakabhaka nobomvu). Ii-electron kunye nee-excitons kwi-graphene zidityaniswe ngamandla e-Coulomb.
(a) Ukuxhomekeka kobushushu bomsantsa we-superconducting kwinkqubo edityaniswe ne-bogolon ngokulungiswa kobushushu (umgca onamachaphaza) kwaye ngaphandle kokulungiswa kobushushu (umgca oqinileyo). (b) Ubushushu obubalulekileyo botshintsho lwe-superconducting njengomsebenzi woxinano lwe-condensate kwiintsebenziswano ezidityaniswe ne-bogolon kunye nolungiso lobushushu (umgca obomvu onamachaphaza) kunye nolungenalo (umgca omnyama oqinileyo). Umgca oluhlaza okwesibhakabhaka onamachaphaza ubonisa ubushushu botshintsho lwe-BKT njengomsebenzi woxinano lwe-condensate.
Ukongeza kwi-superconductivity, i-BEC yenye into eyenzekayo kumaqondo obushushu aphantsi. Yimeko yesihlanu yento eyaxelwa kwangaphambili ngu-Einstein ngo-1924. Ukwakheka kwe-BEC kwenzeka xa ii-athomu zamandla aphantsi ziqokelelana kwaye zingena kwimeko efanayo yamandla, eli licandelo lophando olunzulu kwi-condensed matter physics. Inkqubo ye-hybrid Bose-Fermi ngokusisiseko imele ukusebenzisana komaleko wee-electron kunye nomaleko wee-bosons, ezifana nee-excitons ezingathanga ngqo, ii-exciton-polarons, njl. Ukusebenzisana phakathi kwee-particles ze-Bose kunye ne-Fermi kukhokelele kwiintlobo ngeentlobo zeziganeko ezintsha nezinomdla, ezavusa umdla wamaqela omabini. Imbono esisiseko nejolise kwisicelo.
Kulo msebenzi, abaphandi baxele ngendlela entsha yokwenza i-superconducting kwi-graphene, ebangelwa kukusebenzisana phakathi kwee-electron kunye "nee-bogolons" endaweni yee-phonon kwinkqubo eqhelekileyo ye-BCS. Ii-Bogolons okanye ii-Bogoliubov quasiparticles zii-excitations kwi-BEC, ezineempawu ezithile zee-particles. Ngaphakathi kweendawo ezithile zeparameter, le ndlela ivumela ubushushu obubalulekileyo be-superconducting kwi-graphene ukuba bufikelele kwi-70 Kelvin. Abaphandi baphuhlise nethiyori entsha ye-BCS encinci egxile ngokukodwa kwiinkqubo ezisekwe kwi-graphene entsha ye-hybrid. Imodeli abayicebisileyo ikwaqikelela ukuba iipropati ze-superconducting zinokwanda ngobushushu, nto leyo ebangela ukuxhomekeka kobushushu obungengo-monotonic kwi-superconducting gap.
Ukongeza, izifundo zibonise ukuba ukusasazeka kweDirac kwegraphene kugcinwe kule nkqubo exhaswa yi-bogolon. Oku kubonisa ukuba le ndlela yokwenza izinto ibandakanya ii-electron ezine-relativistic dispersion, kwaye le nto ayizange ihlolwe kakuhle kwi-condensed matter physics.
Lo msebenzi utyhila enye indlela yokufezekisa i-superconductivity yobushushu obuphezulu. Kwangaxeshanye, ngokulawula iipropati ze-condensate, sinokulungisa i-superconductivity ye-graphene. Oku kubonisa enye indlela yokulawula izixhobo ze-superconductivity kwixesha elizayo.
Ixesha lokuthumela: Julayi-16-2021 
