Mun gode da ziyartar nature.com. Kuna amfani da sigar burauza mai ƙarancin tallafi ga CSS. Don samun mafi kyawun ƙwarewa, muna ba da shawarar ku yi amfani da sabon burauza (ko ku kashe yanayin daidaitawa a cikin Internet Explorer). A halin yanzu, don tabbatar da ci gaba da tallafi, muna nuna shafin ba tare da salo da JavaScript ba.
Mun bayar da rahoton tasirin photovoltaic mai ban mamaki a cikin yumbu YBa2Cu3O6.96 (YBCO) tsakanin 50 zuwa 300 K wanda hasken shuɗi-laser ya haifar, wanda ke da alaƙa kai tsaye da superconductivity na YBCO da haɗin lantarki na ƙarfe na YBCO. Akwai juyawar polarity don ƙarfin lantarki na kewaye mai buɗewa Voc da current na ɗan gajeren kewaye Isc lokacin da YBCO ke fuskantar sauyawa daga superconducting zuwa yanayin juriya. Mun nuna cewa akwai ƙarfin lantarki a fadin superconductor-na al'ada na haɗin ƙarfe, wanda ke ba da ƙarfin rabuwa don nau'ikan electron-hole da aka haifar da hoto. Wannan ƙarfin haɗin yana kaiwa daga YBCO zuwa electrode na ƙarfe lokacin da YBCO ke superconducting kuma yana canzawa zuwa akasin haka lokacin da YBCO ba ya superconducting. Asalin ƙarfin yana iya dangantawa da tasirin kusanci a haɗin ƙarfe-superconductor lokacin da YBCO ke superconductor kuma an kiyasta ƙimarsa ta kasance ~10-8 mV a 50 K tare da ƙarfin laser na 502 mW/cm2. Haɗakar kayan YBCO na nau'in p a yanayin da ya dace da kayan nau'in n Ag-manna yana samar da mahaɗin quasi-pn wanda ke da alhakin halayen photovoltaic na yumbu YBCO a yanayin zafi mai yawa. Bincikenmu na iya buɗe hanyar zuwa sabbin aikace-aikacen na'urorin lantarki na photon da kuma ƙara haske kan tasirin kusanci a mahaɗin superconductor-metal.
An bayar da rahoton ƙarfin lantarki da aka haifar da hoto a cikin manyan masu sarrafa wutar lantarki masu zafi a farkon shekarun 1990 kuma an yi bincike sosai tun daga lokacin, duk da haka yanayinsa da tsarinsa ba su daidaita ba1,2,3,4,5. An yi nazari sosai kan fim ɗin YBa2Cu3O7-δ (YBCO) na siriri6,7,8, musamman, a cikin nau'in ƙwayar photovoltaic (PV) saboda gibin makamashi mai daidaitawa9,10,11,12,13. Duk da haka, juriya mai yawa na substrate koyaushe yana haifar da ƙarancin ingancin juyawa na na'urar kuma yana ɓoye manyan halayen PV na YBCO8. A nan mun bayar da rahoton tasirin photovoltaic mai ban mamaki wanda hasken shuɗi-laser (λ = 450 nm) ya haifar a cikin yumbu YBa2Cu3O6.96 (YBCO) tsakanin 50 da 300 K (Tc ~ 90 K). Mun nuna cewa tasirin PV yana da alaƙa kai tsaye da superconductivity na YBCO da yanayin haɗin lantarki na YBCO-metallic electrode. Akwai juyawar polarity ga ƙarfin lantarki na da'irar buɗewa Voc da kuma yanayin juriya na ɗan gajeren lokaci lokacin da YBCO ke fuskantar sauyawa daga matakin superconducting zuwa yanayin juriya. Ana ba da shawarar cewa akwai ƙarfin lantarki a fadin superconductor-normal metal interface, wanda ke ba da ƙarfin rabuwa don nau'ikan electron-hole da aka haifar da photo-induced. Wannan ƙarfin haɗin gwiwa yana kaiwa daga YBCO zuwa ƙarfe electrode lokacin da YBCO ke superconducting kuma yana canzawa zuwa akasin haka lokacin da samfurin ya zama ba superconducting ba. Asalin ƙarfin yana iya kasancewa da alaƙa ta halitta da tasirin kusanci14,15,16,17 a cikin haɗin ƙarfe-superconductor lokacin da YBCO ke superconducting kuma an kiyasta ƙimarsa ta zama ~10−8 mV a 50 K tare da ƙarfin laser na 502 mW/cm2. Haɗakar kayan p-type YBCO a yanayin al'ada tare da kayan n-type Ag-manna yana samar da, wataƙila, mahaɗin quasi-pn wanda ke da alhakin halayen PV na yumbu YBCO a yanayin zafi mai yawa. Abubuwan da muka lura sun ƙara haske kan asalin tasirin PV a cikin yumburan YBCO masu zafi mai zafi da kuma share hanyar amfani da shi a cikin na'urorin lantarki kamar na'urar gano haske mai sauri da sauransu.
Siffa ta 1a–c ta nuna cewa halayen IV na samfurin yumbu na YBCO a 50 K. Ba tare da hasken haske ba, ƙarfin lantarki a kan samfurin ya kasance a sifili tare da canjin wutar lantarki, kamar yadda ake tsammani daga kayan superconducting. Tasirin photovoltaic bayyananne yana bayyana lokacin da aka mayar da hasken laser zuwa cathode (Hoto na 1a): lanƙwasa na IV da ke daidai da axis na I suna motsawa ƙasa tare da ƙaruwar ƙarfin laser. A bayyane yake cewa akwai ƙarfin lantarki mai haifar da hoto mara kyau koda ba tare da wani current ba (wanda galibi ake kira voltage na kewaye mai buɗewa Voc). Gefen sifili na lanƙwasa na IV yana nuna cewa samfurin har yanzu yana da superconducting a ƙarƙashin hasken laser.
(a–c) da 300 K (e–g). An samo ƙimar V(I) ta hanyar share wutar lantarki daga −10 mA zuwa +10 mA a cikin injin tsabtace iska. An gabatar da wani ɓangare na bayanan gwaji kawai don a fayyace. a, Halayen wutar lantarki na YBCO da aka auna da tabo na laser da aka sanya a cathode (i). Duk lanƙwasa na IV layuka ne madaidaiciya a kwance suna nuna cewa samfurin har yanzu yana da iko sosai tare da hasken laser. Lanƙwasa yana motsawa ƙasa tare da ƙaruwar ƙarfin laser, yana nuna cewa akwai yuwuwar mummunan (Voc) tsakanin jagororin ƙarfin lantarki guda biyu koda da sifili na wutar lantarki. Lanƙwasa na IV ba su canzawa ba lokacin da aka karkatar da laser a tsakiyar samfurin a ether 50 K (b) ko 300 K (f). Layin kwance yana motsawa sama yayin da anode ke haskakawa (c). An nuna samfurin tsari na mahaɗin ƙarfe-superconductor a 50 K a cikin d. An ba da halayen wutar lantarki na yanayin YBCO na yau da kullun a 300 K da aka auna tare da hasken laser da aka nuna a cathode da anode a cikin e da g bi da bi. Sabanin sakamakon da aka samu a 50 K, gangaren layukan madaidaiciya mara sifili yana nuna cewa YBCO yana cikin yanayin al'ada; ƙimar Voc ta bambanta da ƙarfin haske a akasin alkibla, tana nuna wata hanyar raba caji daban. Tsarin hanyar sadarwa mai yuwuwa a 300 K an nuna shi a cikin hj. Ainihin hoton samfurin tare da jagora.
YBCO mai arzikin iskar oxygen a yanayin superconducting zai iya shan kusan cikakken hasken rana saboda ƙaramin gibin makamashinsa (Misali)9,10, ta haka ne ke ƙirƙirar nau'ikan ramukan electron (e-h). Don samar da wutar lantarki mai buɗewa ta hanyar shan photons, yana da mahimmanci a raba nau'ikan eh da aka samar ta hanyar hoto kafin sake haɗuwa ya faru18. Voc mara kyau, dangane da cathode da anode kamar yadda aka nuna a Hoto na 1i, yana nuna cewa akwai yuwuwar lantarki a fadin hanyar haɗin ƙarfe-superconductor, wanda ke share electrons zuwa anode da ramuka zuwa cathode. Idan haka ne, ya kamata kuma a sami yuwuwar nuna daga superconductor zuwa ƙarfe electrode a anode. Saboda haka, za a sami Voc mai kyau idan an haskaka yankin samfurin kusa da anode. Bugu da ƙari, bai kamata a sami ƙarfin lantarki da aka haifar da hoto ba lokacin da aka nuna wurin laser zuwa wurare da ke nesa da electrodes. Tabbas haka lamarin yake kamar yadda za a iya gani daga Hoto na 1b, c!.
Lokacin da wurin haske ya motsa daga na'urar lantarki ta cathode zuwa tsakiyar samfurin (kimanin mm 1.25 baya ga hanyoyin haɗin), babu wani bambancin lanƙwasa na IV ko babu Voc da za a iya gani tare da ƙara ƙarfin laser zuwa matsakaicin ƙimar da ake da shi (Hoto na 1b). A zahiri, ana iya danganta wannan sakamakon da ƙarancin tsawon rai na masu ɗaukar hoto da rashin ƙarfin rabuwa a cikin samfurin. Ana iya ƙirƙirar nau'ikan ramukan lantarki duk lokacin da aka haskaka samfurin, amma yawancin nau'ikan e-h za a lalata su kuma ba a lura da tasirin photovoltaic ba idan wurin laser ya faɗi a wurare masu nisa da kowane ɗayan electrodes. Matsar da wurin laser zuwa ga electrodes na anode, lanƙwasa na IV suna tafiya daidai da axis na I suna motsawa sama tare da ƙaruwar ƙarfin laser (Hoto na 1c). Irin wannan filin lantarki da aka gina a ciki yana nan a cikin mahaɗin ƙarfe-superconductor a anode. Duk da haka, electrode na ƙarfe yana haɗuwa da jagora mai kyau na tsarin gwaji a wannan karon. An tura ramukan da laser ya samar zuwa ga gubar anode don haka ana ganin Voc mai kyau. Sakamakon da aka gabatar a nan ya ba da shaida mai ƙarfi cewa akwai yuwuwar haɗin gwiwa da ke nuna daga superconductor zuwa ƙarfe electrode.
An nuna tasirin photovoltaic a cikin yumbu YBa2Cu3O6.96 a 300 K a cikin Hoto na 1e–g. Ba tare da hasken haske ba, lanƙwasa ta IV na samfurin shine layi madaidaiciya wanda ke ratsa asalin. Wannan layin madaidaiciya yana motsawa sama daidai da na asali tare da ƙaruwar ƙarfin laser wanda ke haskakawa a kan hanyoyin cathode (Hoto na 1e). Akwai lokuta biyu masu iyakancewa na sha'awa ga na'urar photovoltaic. Yanayin gajeren da'ira yana faruwa ne lokacin da V = 0. Ana kiran wutar lantarki a wannan yanayin da gajeren da'ira (Isc). Lamarin iyakance na biyu shine yanayin buɗe da'ira (Voc) wanda ke faruwa lokacin da R→∞ ko kuma wutar lantarki sifili ne. Hoto na 1e ya nuna a sarari cewa Voc yana da kyau kuma yana ƙaruwa tare da ƙaruwar ƙarfin haske, sabanin sakamakon da aka samu a 50 K; yayin da aka lura da mummunan Isc yana ƙaruwa da girma tare da hasken haske, halayyar yau da kullun ta ƙwayoyin rana na yau da kullun.
Hakazalika, idan aka nuna hasken laser a wurare masu nisa da electrodes, lanƙwasa V(I) ba ta dogara da ƙarfin laser ba kuma babu wani tasirin photovoltaic da ya bayyana (Hoto na 1f). Kamar aunawa a 50 K, lanƙwasa na IV suna motsawa zuwa akasin alkibla yayin da aka haskaka wutar lantarki ta anode (Hoto na 1g). Duk waɗannan sakamakon da aka samu don wannan tsarin manna YBCO-Ag a 300 K tare da hasken laser a wurare daban-daban na samfurin sun yi daidai da yuwuwar haɗin gwiwa akasin wanda aka gani a 50 K.
Yawancin electrons suna taruwa a cikin Cooper a cikin superconductor YBCO ƙasa da zafin canjinsa na Tc. Yayin da yake cikin ƙarfe electrode, duk electrons suna ci gaba da kasancewa a cikin siffa ta mufuradi. Akwai babban gradient mai yawa ga electrons guda ɗaya da Cooper a kusa da haɗin ƙarfe-superconductor. Elektrons guda ɗaya masu ɗaukar nauyi a cikin kayan ƙarfe za su bazu zuwa yankin superconductor, yayin da Cooper-pairs masu ɗaukar nauyi a yankin YBCO za su bazu zuwa yankin ƙarfe. Yayin da Cooper ke ɗaukar ƙarin caji kuma suna da motsi mafi girma fiye da electrons guda ɗaya suna bazuwa daga YBCO zuwa yankin ƙarfe, ana barin atoms masu caji mai kyau a baya, wanda ke haifar da filin lantarki a yankin cajin sarari. Alkiblar wannan filin lantarki an nuna shi a cikin zane mai zane Hoto na 1d. Hasken photon da ya faru kusa da yankin cajin sarari na iya ƙirƙirar nau'ikan eh waɗanda za a raba su kuma a share su suna samar da photocurrent a cikin juzu'in bias. Da zarar electrons sun fita daga filin lantarki da aka gina, ana haɗa su zuwa biyu kuma suna gudana zuwa ɗayan electrode ba tare da juriya ba. A wannan yanayin, Voc ya saba da polarity da aka riga aka saita kuma yana nuna ƙimar mara kyau lokacin da hasken laser ya nuna yankin da ke kewaye da electrode mara kyau. Daga ƙimar Voc, ana iya kimanta yuwuwar da ke fadin mahaɗin: nisan da ke tsakanin jagororin ƙarfin lantarki guda biyu d shine ~5 × 10−3 m, kauri na mahaɗin ƙarfe-superconductor, di, ya kamata ya zama daidai da tsarin girma da tsawon haɗin kai na superconductor YBCO (~1 nm)19,20, ɗauki ƙimar Voc = 0.03 mV, ana kimanta yuwuwar Vms a mahaɗin ƙarfe-superconductor zuwa ~10−11 V a 50 K tare da ƙarfin laser na 502 mW/cm2, ta amfani da lissafi,
Muna son jaddadawa a nan cewa ba za a iya bayyana ƙarfin lantarki da aka haifar da hoton ta hanyar tasirin zafi na hoto ba. An tabbatar da shi ta hanyar gwaji cewa ma'aunin Seebeck na superconductor YBCO shine Ss = 021. Ma'aunin Seebeck na wayoyi na jan ƙarfe yana cikin kewayon SCu = 0.34–1.15 μV/K3. Zafin wayar jan ƙarfe a wurin laser za a iya ɗaga shi da ƙaramin adadin 0.06 K tare da matsakaicin ƙarfin laser da ake samu a 50 K. Wannan zai iya samar da ƙarfin thermoelectric na 6.9 × 10−8 V wanda girman umarni uku ya fi ƙasa da na Voc da aka samu a Hoto na 1 (a). A bayyane yake cewa tasirin thermoelectric ya yi ƙanƙanta don bayyana sakamakon gwaji. A zahiri, bambancin zafin jiki saboda hasken laser zai ɓace cikin ƙasa da minti ɗaya don haka za a iya yin watsi da gudummawar tasirin zafi cikin aminci.
Wannan tasirin hasken YBCO a zafin ɗaki ya nuna cewa akwai wata hanyar raba caji daban a nan. Babban aikin YBCO a yanayin al'ada abu ne na nau'in p tare da ramuka a matsayin mai ɗaukar caji22,23, yayin da ƙarfe Ag-manna yana da halaye na kayan nau'in n. Kamar mahaɗan pn, yaɗuwar electrons a cikin manna azurfa da ramuka a cikin yumbu YBCO zai samar da filin lantarki na ciki wanda ke nuna yumbu YBCO a mahaɗin (Hoto na 1h). Wannan filin ciki ne ke samar da ƙarfin rabuwa kuma yana haifar da Voc mai kyau da Isc mara kyau don tsarin manna YBCO-Ag a zafin ɗaki, kamar yadda aka nuna a Hoto na 1e. A madadin haka, Ag-YBCO na iya samar da mahaɗin Schottky na nau'in p wanda kuma yana haifar da yuwuwar haɗin gwiwa tare da irin wannan polarity kamar yadda aka nuna a cikin samfurin da aka gabatar a sama24.
Don bincika cikakken tsarin juyin halitta na halayen photovoltaic yayin canjin superconducting na YBCO, an auna lanƙwasa na IV na samfurin a 80 K tare da zaɓaɓɓun ƙarfin laser da ke haskakawa a cikin cathode electrode (Hoto na 2). Ba tare da hasken laser ba, ƙarfin lantarki a kan samfurin yana kasancewa a sifili ba tare da la'akari da halin yanzu ba, yana nuna yanayin superconducting na samfurin a 80 K (Hoto na 2a). Kamar bayanan da aka samu a 50 K, lanƙwasa na IV suna tafiya ƙasa tare da ƙaruwar ƙarfin laser har sai an kai ƙimar Pc mai mahimmanci. Sama da wannan ƙarfin laser mai mahimmanci (Pc), superconductor yana fuskantar sauyawa daga matakin superconducting zuwa matakin juriya; ƙarfin lantarki yana fara ƙaruwa tare da halin yanzu saboda bayyanar juriya a cikin superconductor. Sakamakon haka, lanƙwasa na IV ya fara haɗuwa da axis na I da axis na V wanda ke haifar da Voc mara kyau da Isc mai kyau da farko. Yanzu samfurin yana kama da yana cikin yanayi na musamman inda polarity na Voc da Isc yana da matuƙar tasiri ga ƙarfin haske; tare da ƙaramin ƙaruwa a cikin ƙarfin haske, Isc yana canzawa daga positive zuwa negative da Voc daga negative zuwa positive, yana wucewa ta asali (babban ƙarfin halayen photovoltaic, musamman ƙimar Isc, zuwa haske mai haske za a iya gani a sarari a cikin Hoto na 2b). A mafi girman ƙarfin laser da ake da shi, lanƙwasa na IV suna da niyyar zama daidai da juna, suna nuna yanayin da aka saba da samfurin YBCO.
Cibiyar tabo ta laser tana kewaye da na'urorin lantarki na cathode (duba Hoto na 1i). a, Layukan IV na YBCO da aka haskaka tare da ƙarfin laser daban-daban. b (sama), Dogaro da ƙarfin Laser na ƙarfin lantarki na kewaye mai buɗewa Voc da kuma gajeren wutar lantarki ta kewaye mai gajeren lokaci Isc. Ba za a iya samun ƙimar Isc a ƙarancin ƙarfin haske ba (<110 mW/cm2) saboda layukan IV suna daidai da axis na I lokacin da samfurin yake cikin yanayin superconducting. b (ƙasa), juriya daban-daban azaman aikin ƙarfin Laser.
An nuna dogaro da ƙarfin laser na Voc da Isc a 80 K a cikin Hoto na 2b (sama). Ana iya tattauna halayen photovoltaic a yankuna uku na ƙarfin haske. Yankin farko yana tsakanin 0 da Pc, inda YBCO ke yin superconducting, Voc yana da korau kuma yana raguwa (ƙaruwar ƙimar gaba ɗaya) tare da ƙarfin haske kuma yana kaiwa mafi ƙaranci a Pc. Yankin na biyu yana daga Pc zuwa wani babban ƙarfi na P0, inda Voc ke ƙaruwa yayin da Isc ke raguwa tare da ƙaruwar ƙarfin haske kuma duka biyun suna kaiwa sifili a P0. Yankin na uku yana sama da P0 har sai yanayin YBCO na yau da kullun ya isa. Kodayake duka Voc da Isc sun bambanta tare da ƙarfin haske kamar yadda yake a yanki na 2, suna da akasin polarity sama da babban ƙarfin P0. Muhimmancin P0 ya ta'allaka ne da cewa babu tasirin photovoltaic kuma tsarin rabuwar caji yana canzawa ta hanyar inganci a wannan takamaiman lokacin. Samfurin YBCO ya zama ba superconducting a cikin wannan kewayon ƙarfin haske amma yanayin yau da kullun da ba a isa ba tukuna.
A bayyane yake cewa halayen hasken rana na tsarin suna da alaƙa da ƙarfin lantarki na YBCO da kuma canjinsa na superconductivity. An nuna bambancin juriya, dV/dI, na YBCO a cikin Hoto na 2b (ƙasa) a matsayin aikin ƙarfin laser. Kamar yadda aka ambata a baya, ƙarfin lantarki da aka gina a cikin haɗin gwiwa saboda wuraren watsawa na Cooper pair daga superconductor zuwa ƙarfe. Kamar yadda aka gani a 50 K, tasirin hasken rana yana ƙaruwa tare da ƙaruwar ƙarfin laser daga 0 zuwa Pc. Lokacin da ƙarfin laser ya kai ƙima kaɗan sama da Pc, lanƙwasa na IV ya fara karkata kuma juriyar samfurin ta fara bayyana, amma ba a canza polarity na ƙarfin haɗin gwiwa ba tukuna. An binciki tasirin motsin gani akan superconductivity a yankin da ake gani ko kusa da IR. Yayin da tsari na asali shine a wargaza nau'ikan Cooper da lalata superconductivity25,26, a wasu lokuta ana iya haɓaka canjin superconductivity27,28,29, sabbin matakai na superconductivity ma ana iya haifar da su30. Rashin ƙarfin lantarki a Pc za a iya danganta shi da karyewar haɗin gwiwa da aka haifar da hoto. A wurin P0, yuwuwar da ke tsakanin haɗin gwiwa ta zama sifili, wanda ke nuna yawan caji a ɓangarorin biyu na haɗin gwiwa ya kai matakin ɗaya a ƙarƙashin wannan ƙarfin haske. Ƙarin ƙaruwa a cikin ƙarfin laser yana haifar da ƙarin nau'ikan Cooper da aka lalata kuma YBCO a hankali ana mayar da shi zuwa kayan p. Maimakon yaduwar electron da Cooper, fasalin haɗin gwiwa yanzu ana tantance shi ta hanyar yaduwar electron da rami wanda ke haifar da juyawar polarity na filin lantarki a cikin haɗin gwiwa kuma sakamakon haka Voc mai kyau (kwatanta Hoto na 1d, h). A cikin babban ƙarfin laser, bambancin juriya na YBCO yana cika zuwa ƙimar da ta dace da yanayin al'ada kuma duka Voc da Isc suna bambanta a layi tare da ƙarfin laser (Hoto na 2b). Wannan lura ya nuna cewa hasken laser akan yanayin al'ada YBCO ba zai sake canza juriyarsa da fasalin haɗin superconductor-metal ba amma kawai yana ƙara yawan haɗin electron-hole.
Domin bincika tasirin zafin jiki akan halayen photovoltaic, an haskaka tsarin ƙarfe-superconductor a cathode tare da shuɗin laser mai ƙarfi 502 mW/cm2. An ba da lanƙwasa na IV da aka samu a zafin da aka zaɓa tsakanin 50 da 300 K a cikin Hoto na 3a. Ana iya samun ƙarfin wutar lantarki na kewaye mai buɗewa Voc, current na kewaye mai gajeren lokaci Isc da juriyar bambanci daga waɗannan lanƙwasa na IV kuma an nuna su a Hoto na 3b. Ba tare da hasken haske ba, duk lanƙwasa na IV da aka auna a yanayin zafi daban-daban suna wucewa ta asali kamar yadda aka zata (inset na Hoto na 3a). Halayen IV suna canzawa sosai tare da ƙaruwar zafin jiki lokacin da tsarin ya haskaka ta hanyar hasken laser mai ƙarfi (502 mW/cm2). A ƙananan zafin jiki lanƙwasa na IV layuka ne madaidaiciya daidai da axis na I tare da ƙimar Voc mara kyau. Wannan lanƙwasa yana motsawa sama tare da ƙaruwar zafin jiki kuma a hankali yana juyawa zuwa layi tare da gangara mara sifili a yanayin zafi mai mahimmanci Tcp (Hoto na 3a (sama)). Da alama duk lanƙwasa halayen IV suna juyawa a kusa da wani wuri a cikin kwata na uku. Voc yana ƙaruwa daga ƙimar mara kyau zuwa mai kyau yayin da Isc ke raguwa daga ƙimar mara kyau zuwa mara kyau. Sama da zafin canjin superconductor na asali Tc na YBCO, lanƙwasa na IV yana canzawa daban-daban tare da zafin jiki (ƙasa na Hoto na 3a). Da farko, tsakiyar juyawa na lanƙwasa na IV yana motsawa zuwa quadrant na farko. Na biyu, Voc yana ci gaba da raguwa kuma Isc yana ƙaruwa tare da yanayin zafi mai ƙaruwa (saman Hoto na 3b). Na uku, gangaren lanƙwasa na IV yana ƙaruwa a layi tare da zafin jiki wanda ke haifar da ƙimar juriya mai kyau ga YBCO (ƙasa na Hoto na 3b).
Dogaro da yanayin zafi na halayen photovoltaic don tsarin manna YBCO-Ag a ƙarƙashin hasken laser 502 mW/cm2.
An sanya tsakiyar tabo na laser a kusa da na'urorin lantarki na cathode (duba Hoto na 1i). a, lanƙwasa na IV da aka samu daga 50 zuwa 90 K (sama) da kuma daga 100 zuwa 300 K (ƙasa) tare da ƙaruwar zafin jiki na 5 K da 20 K, bi da bi. Sanya a yana nuna halayen IV a yanayin zafi da yawa a cikin duhu. Duk lanƙwasa suna ketare wurin asali. b, ƙarfin lantarki na da'irar buɗewa Voc da kuma yanayin zafi na ɗan gajeren lokaci Isc (sama) da juriyar bambanci, dV/dI, na YBCO (ƙasa) azaman aikin zafin jiki. Ba a bayar da zafin canji na sifili mai jurewa ba Tcp saboda yana kusa da Tc0 sosai.
Za a iya gane yanayin zafi guda uku masu mahimmanci daga Hoto na 3b: Tcp, wanda a sama YBCO ya zama ba superconducting ba; Tc0, wanda duka Voc da Isc suka zama sifili da Tc, ainihin zafin canjin superconducting na YBCO ba tare da laser radiation ba. A ƙasan Tcp ~ 55 K, YBCO mai laser radiation yana cikin yanayin superconducting tare da yawan haɗin Cooper. Tasirin laser radiation shine rage yawan juriya na superconducting daga sifili superconducting zafin jiki daga 89 K zuwa ~55 K (ƙasa na Hoto na 3b) ta hanyar rage yawan haɗin Cooper da kuma samar da wutar lantarki da halin yanzu. Ƙara yawan zafin jiki kuma yana rushe haɗin Cooper wanda ke haifar da ƙarancin damar a cikin interface. Saboda haka, cikakken ƙimar Voc zai zama ƙarami, kodayake ana amfani da irin wannan ƙarfin hasken laser. Ƙarfin haɗin zai zama ƙarami da ƙarami tare da ƙarin ƙaruwa a zafin jiki kuma ya kai sifili a Tc0. Babu tasirin photovoltaic a wannan wuri na musamman saboda babu filin ciki don raba haɗin electron-hole da photo-induced. Juyawar polarity na yuwuwar yana faruwa sama da wannan zafin jiki mai mahimmanci yayin da yawan caji kyauta a cikin manna Ag ya fi na YBCO girma wanda a hankali ake mayar da shi zuwa kayan nau'in p. A nan muna son jaddada cewa juyar da polarity na Voc da Isc yana faruwa nan da nan bayan canjin juriya na sifili, ba tare da la'akari da dalilin sauyin ba. Wannan lura ya bayyana a sarari, a karon farko, alaƙar da ke tsakanin superconductivity da tasirin photovoltaic da ke da alaƙa da yuwuwar haɗin ƙarfe-superconductor. Yanayin wannan yuwuwar a cikin superconductor-al'ada ƙarfe interface ya kasance abin da aka mayar da hankali a kai a cikin shekaru da yawa da suka gabata amma akwai tambayoyi da yawa da har yanzu ana jiran a amsa su. Ma'aunin tasirin photovoltaic na iya zama hanya mai tasiri don bincika cikakkun bayanai (kamar ƙarfinsa da polarity da sauransu) na wannan muhimmiyar yuwuwar don haka ya haskaka tasirin kusancin superconductor mai zafi.
Ƙarin ƙaruwa a zafin jiki daga Tc0 zuwa Tc yana haifar da ƙaramin yawan nau'ikan Cooper da haɓakawa a cikin ƙarfin haɗin gwiwa da kuma girman Voc. A Tc yawan haɗin Cooper ya zama sifili kuma ƙarfin ginawa a cikin haɗin gwiwa ya kai matsakaicin, wanda ke haifar da matsakaicin Voc da mafi ƙarancin Isc. Saurin ƙaruwar Voc da Isc (ƙimar cikakke) a cikin wannan kewayon zafin jiki ya yi daidai da canjin superconductor wanda aka faɗaɗa daga ΔT ~ 3 K zuwa ~ 34 K ta hanyar hasken laser na ƙarfi 502 mW/cm2 (Hoto na 3b). A cikin yanayin al'ada da ke sama da Tc, ƙarfin wutar lantarki na kewaye na buɗewa Voc yana raguwa tare da zafin jiki (saman Hoto na 3b), yayi kama da yanayin layi na Voc don ƙwayoyin rana na yau da kullun bisa ga haɗin pn31,32,33. Kodayake canjin Voc tare da zafin jiki (−dVoc/dT), wanda ya dogara sosai akan ƙarfin laser, ya fi ƙanƙanta fiye da na ƙwayoyin rana na yau da kullun, ƙimar zafin jiki na Voc don haɗin YBCO-Ag yana da tsari iri ɗaya da na ƙwayoyin rana. Ruwan kwararar iskar lantarki na mahaɗin pn don na'urar ƙwayoyin rana ta yau da kullun yana ƙaruwa tare da ƙaruwar zafin jiki, wanda ke haifar da raguwar Voc yayin da zafin jiki ke ƙaruwa. Lanƙwasa masu layi na IV da aka lura da wannan tsarin Ag-superconductor, da farko ƙaramin ƙarfin haɗin gwiwa ne kuma na biyu haɗin baya-da-baya na heterojunctions guda biyu, yana sa ya zama da wahala a tantance kwararar iskar lantarki. Duk da haka, yana da yuwuwar cewa dogaro da zafin jiki iri ɗaya na kwararar iskar lantarki shine ke da alhakin halayen Voc da aka lura a cikin gwajinmu. Dangane da ma'anar, Isc shine kwararar lantarki da ake buƙata don samar da wutar lantarki mara kyau don rama Voc don jimlar ƙarfin lantarki ya zama sifili. Yayin da zafin jiki ke ƙaruwa, Voc yana ƙarami don haka ana buƙatar ƙarancin kwararar iska don samar da wutar lantarki mara kyau. Bugu da ƙari, juriyar YBCO yana ƙaruwa a layi tare da zafin jiki sama da Tc (ƙasa na Hoto na 3b), wanda kuma yana ba da gudummawa ga ƙaramin ƙimar Isc a yanayin zafi mai yawa.
Lura cewa sakamakon da aka bayar a Fig 2,3 an samo shi ne ta hanyar amfani da hasken laser a yankin da ke kewaye da na'urorin lantarki na cathode. An kuma maimaita ma'auni tare da tabo na laser da aka sanya a anode kuma an lura da irin waɗannan halaye na IV kuma an lura da halayen photovoltaic sai dai cewa an juya polarity na Voc da Isc a wannan yanayin. Duk waɗannan bayanan suna haifar da wata hanyar tasirin photovoltaic, wacce ke da alaƙa da haɗin superconductor-metal.
A taƙaice, an auna halayen IV na tsarin manna YBCO-Ag mai ƙarfin lantarki mai haske ta hanyar laser a matsayin ayyukan zafin jiki da ƙarfin laser. An lura da tasirin photovoltaic mai ban mamaki a cikin kewayon zafin jiki daga 50 zuwa 300 K. An gano cewa halayen photovoltaic suna da alaƙa sosai da ƙarfin lantarki na yumburan YBCO. Juyawar polarity na Voc da Isc yana faruwa nan da nan bayan canjin da aka haifar da hoto zuwa canjin da ba na superconducting ba. Dogaro da zafin jiki na Voc da Isc da aka auna a madaidaicin ƙarfin laser yana nuna juyawar polarity daban-daban a zafin jiki mai mahimmanci a sama wanda samfurin ya zama mai juriya. Ta hanyar gano wurin laser zuwa wani ɓangare na samfurin, mun nuna cewa akwai ƙarfin lantarki a fadin hanyar haɗin, wanda ke ba da ƙarfin rabuwa don nau'ikan ramin electron da aka haifar da hoto. Wannan ƙarfin haɗin yana kaiwa daga YBCO zuwa lantarki na ƙarfe lokacin da YBCO ke superconducting kuma yana canzawa zuwa akasin haka lokacin da samfurin ya zama mara superconducting. Asalin yuwuwar na iya kasancewa da alaƙa ta halitta da tasirin kusanci a mahaɗin ƙarfe-superconductor lokacin da YBCO ke yin superconductor kuma an kiyasta ya kai ~10−8 mV a 50 K tare da ƙarfin laser na 502 mW/cm2. Hulɗar kayan p-type YBCO a yanayin al'ada tare da kayan n-type Ag-manna yana samar da mahaɗin quasi-pn wanda ke da alhakin halayen photovoltaic na yumbu YBCO a yanayin zafi mai yawa. Abubuwan da aka lura a sama sun haskaka tasirin PV a cikin yumbu YBCO masu yawan zafin jiki mai yawa kuma suna buɗe hanyar zuwa sabbin aikace-aikace a cikin na'urorin optoelectronic kamar na'urar gano haske mai sauri da na'urar gano photon guda ɗaya.
An yi gwaje-gwajen tasirin photovoltaic akan samfurin yumbu na YBCO mai kauri mm 0.52 da siffar murabba'i mai siffar murabba'i 8.64 × 2.26 mm2 kuma an haskaka shi da hasken laser mai ci gaba da raƙuman ruwa (λ = 450 nm) tare da girman tabo na laser na mm 1.25 a radius. Yin amfani da samfurin fim mai girma maimakon siriri yana ba mu damar yin nazarin halayen photovoltaic na superconductor ba tare da fuskantar tasirin rikitarwa na substrate6,7 ba. Bugu da ƙari, kayan da aka yi amfani da su na iya zama masu dacewa don sauƙin tsarin shiri da ƙarancin farashi. Wayoyin jan ƙarfe suna haɗuwa akan samfurin YBCO tare da manna azurfa wanda ke samar da lantarki huɗu masu zagaye kusan diamita na mm 1. Nisa tsakanin electrodes biyu na wutar lantarki shine kusan mm 5. An auna halayen IV na samfurin ta amfani da na'urar auna girgiza (VersaLab, Tsarin Quantum) tare da taga lu'ulu'u na quartz. An yi amfani da hanyar waya huɗu ta yau da kullun don samun lanƙwasa na IV. Matsayin electrodes da wurin laser an nuna su a cikin Hoto na 1i.
Yadda za a ambaci wannan labarin: Yang, F. et al. Asalin tasirin photovoltaic a cikin tukwane masu sarrafa YBa2Cu3O6.96. Sci. Rep. 5, 11504; doi: 10.1038/srep11504 (2015).
Chang, CL, Kleinhammes, A., Moulton, WG & Testardi, Ƙarfin wutar lantarki da laser ya haifar da aka haramta ta LR a cikin YBa2Cu3O7. Phys. Rev. B 41, 11564–11567 (1990).
Kwok, HS, Zheng, JP & Dong, SY Asalin siginar photovoltaic mara kyau a cikin Y-Ba-Cu-O. Phys. Rev. B 43, 6270–6272 (1991).
Wang, LP, Lin, JL, Feng, QR & Wang, GW Ma'aunin ƙarfin lantarki da laser ke haifarwa na Bi-Sr-Ca-Cu-O mai ƙarfin lantarki. Phys. Rev. B 46, 5773–5776 (1992).
Tate, KL, da sauransu. Ƙarfin lantarki da laser ke haifarwa na ɗan lokaci a cikin fina-finan YBa2Cu3O7-x masu zafin ɗaki. J. Appl. Phys. 67, 4375–4376 (1990).
Kwok, HS & Zheng, JP Amsar photovoltaic mara kyau a cikin YBa2Cu3O7. Phys. Rev. B 46, 3692–3695 (1992).
Muraoka, Y., Muramatsu, T., Yamaura, J. & Hiroi, Z. Allurar da aka samar ta hanyar daukar hoto zuwa YBa2Cu3O7−x a cikin wani tsari mai hade da iskar oxygen. Appl. Phys. Lett. 85, 2950–2952 (2004).
Asakura, D. da sauransu. Nazarin watsawar hotuna na siraran fim na YBa2Cu3Oy a ƙarƙashin hasken haske. Phys. Rev. Lett. 93, 247006 (2004).
Yang, F. da sauransu. Tasirin ɗaukar hoto na YBa2Cu3O7-δ/SrTiO3 :Nb heterojunction annealed a cikin matsin lamba daban-daban na iskar oxygen. Mater. Lett. 130, 51–53 (2014).
Aminov, BA da sauransu. Tsarin Gap Biyu a cikin lu'ulu'u guda ɗaya na Yb(Y)Ba2Cu3O7-x. J. Supercond. 7, 361–365 (1994).
Kabanov, VV, Demsar, J., Podobnik, B. & Mihailovic, D. Tsarin shakatawa na Quasiparticle a cikin manyan masu jagoranci tare da tsarin gibin daban-daban: Ka'ida da gwaje-gwaje akan YBa2Cu3O7-δ. Phys. Rev. B 59, 1497–1506 (1999).
Sun, JR, Xiong, CM, Zhang, YZ & Shen, BG Gyara kaddarorin YBa2Cu3O7-δ/SrTiO3 :Nb heterojunction. Appl. Phys. Lett. 87, 222501 (2005).
Kamarás, K., Porter, CD, Doss, MG, Herr, SL & Tanner, DB Sha da kuma superconductivity na excitonic a cikin YBa2Cu3O7-δ. Phys. Rev. Lett. 59, 919–922 (1987).
Yu, G., Heeger, AJ & Stucky, G. Tsarin ɗaukar hoto mai motsi a cikin lu'ulu'u guda ɗaya na YBa2Cu3O6.3 masu ɗaukar hoto: bincika yanayin ƙarfe mai ɗaukar hoto da kuma yanayin ɗaukar hoto mai ƙarfi. Al'umma Mai ƙarfi. 72, 345–349 (1989).
McMillan, WL Tsarin Tunneling na tasirin kusancin superconducting. Phys. Rev. 175, 537–542 (1968).
Guéron, S. da sauransu. An yi bincike kan tasirin kusancin superconducting akan sikelin tsayin mesoscopic. Phys. Rev. Lett. 77, 3025–3028 (1996).
Annunziata, G. & Manske, D. Tasirin kusanci tare da manyan masu jagoranci marasa daidaituwa. Phys. Rev. B 86, 17514 (2012).
Qu, FM da sauransu. Ƙarfin tasirin kusanci mai ƙarfi a cikin tsarin haɗin Pb-Bi2Te3. Sci. Rep. 2, 339 (2012).
Chapin, DM, Fuller, CS & Pearson, GL Sabuwar na'urar daukar hoto ta silicon pn don canza hasken rana zuwa wutar lantarki. J. App. Phys. 25, 676–677 (1954).
Tomimoto, K. Tasirin ƙazanta akan tsawon haɗin kai mai ƙarfi a cikin lu'ulu'u guda ɗaya na YBa2Cu3O6.9 na Zn- ko Ni. Phys. Rev. B 60, 114–117 (1999).
Ando, Y. & Segawa, K. Magnetoresistance na lu'ulu'u guda ɗaya marasa twinned YBa2Cu3Oy a cikin nau'ikan allurar rigakafi masu yawa: dogaro da allurar rami mara kyau dangane da tsawon haɗin kai. Phys. Rev. Lett. 88, 167005 (2002).
Obertelli, SD & Cooper, JR Systematics a cikin ƙarfin thermoelectric na high-T, oxides. Phys. Rev. B 46, 14928–14931, (1992).
Sugai, S. da sauransu. Canjin motsi mai dogaro da yawan jigilar kaya na kololuwar haɗin kai da yanayin phonon na LO a cikin manyan masu sarrafa wutar lantarki na nau'in p-type. Phys. Rev. B 68, 184504 (2003).
Nojima, T. da sauransu. Rage ramuka da tarin electrons a cikin siraran fim ɗin YBa2Cu3Oy ta amfani da dabarar electrochemical: Shaida don yanayin ƙarfe na nau'in n. Phys. Rev. B 84, 020502 (2011).
Tung, RT Ilimin kimiyyar lissafi da sinadarai na tsayin shingen Schottky. Appl. Phys. Lett. 1, 011304 (2014).
Sai-Halasz, GA, Chi, CC, Denenstein, A. & Langenberg, DN Tasirin Karya Tsakanin Ma'aurata Masu Canzawa a Fina-finan Superconductor. Phys. Rev. Lett. 33, 215–219 (1974).
Nieva, G. da sauransu. Inganta yanayin aiki mai ƙarfi wanda aka haifar da hotuna. Appl. Phys. Lett. 60, 2159–2161 (1992).
Kudinov, VI da sauransu. Tsarin ɗaukar hoto mai ɗorewa a cikin fina-finan YBa2Cu3O6+x a matsayin hanyar ɗaukar hoto zuwa matakan ƙarfe da superconducting. Phys. Rev. B 14, 9017–9028 (1993).
Mankowsky, R. da sauransu. Tsarin lattice marasa layi a matsayin tushen ingantaccen yanayin aiki a cikin YBa2Cu3O6.5. Nature 516, 71–74 (2014).
Fausti, D. da sauransu. Superconductivity da haske ya haifar a cikin wani tsari mai layi-layi. Kimiyya 331, 189–191 (2011).
El-Adawi, MK & Al-Nuaim, IA Dogaron aiki na VOC ga ƙwayar hasken rana dangane da ingancinsa sabon tsarin tsaftacewa. 209, 91–96 (2007).
Vernon, SM & Anderson, WA Tasirin zafin jiki a cikin ƙwayoyin hasken rana na silicon na Schottky. Appl. Phys. Lett. 26, 707 (1975).
Katz, EA, Faiman, D. & Tuladhar, SM Dogaro da yanayin zafi ga sigogin na'urar photovoltaic na ƙwayoyin hasken rana na polymer-fullerene a ƙarƙashin yanayin aiki. J. Appl. Phys. 90, 5343–5350 (2002).
Gidauniyar Kimiyyar Halitta ta Ƙasa ta ƙasar Sin (Grant No. 60571063), Ayyukan Bincike na Asali na Lardin Henan, ƙasar Sin (Grant No. 122300410231) ne suka tallafa wa wannan aikin.
FY ne ya rubuta rubutun takardar kuma MYH ta shirya samfurin yumbu na YBCO. FY da MYH sun yi gwajin kuma sun yi nazarin sakamakon. FGC ta jagoranci aikin da fassarar kimiyya ta bayanan. Duk marubuta sun yi bitar rubutun.
An ba da lasisin wannan aikin a ƙarƙashin lasisin Creative Commons Attribution 4.0 International License. Hotunan ko wasu kayan ɓangare na uku a cikin wannan labarin an haɗa su a cikin lasisin Creative Commons na labarin, sai dai idan an nuna akasin haka a cikin layin bashi; idan kayan bai ƙunshi lasisin Creative Commons ba, masu amfani za su buƙaci samun izini daga mai lasisin don sake buga kayan. Don duba kwafin wannan lasisin, ziyarci http://creativecommons.org/licenses/by/4.0/
Yang, F., Han, M. & Chang, F. Asalin tasirin photovoltaic a cikin tukwane masu sarrafa YBa2Cu3O6.96 masu ƙarfin gaske. Sci Rep 5, 11504 (2015). https://doi.org/10.1038/srep11504
Ta hanyar gabatar da sharhi, kun yarda ku bi Sharuɗɗanmu da Jagororin Al'umma. Idan kun ga wani abu mai cin zarafi ko kuma wanda bai bi sharuɗɗa ko jagororinmu ba, don Allah ku sanya masa alama a matsayin wanda bai dace ba.
Lokacin Saƙo: Afrilu-22-2020