Muna amfani da lokaci- da kusurwa-ƙuduri photoemission spectroscopy (tr-ARPES) don bincika canja wurin cajin ultrafast a cikin tsarin heterostructure na epitaxial wanda aka yi da monolayer WS2 da graphene. Wannan heterostructure ya haɗu da fa'idodin semiconductor mai rata kai tsaye tare da ƙaƙƙarfan haɗaɗɗiyar juzu'i-orbit da ma'amala mai ƙarfi mai ƙarfi tare da waɗanda ke ɗaukar nauyin jigilar marasa ƙarfi tare da babban motsi da tsayin juyi. Mun gano cewa, bayan photoexcitation a resonance zuwa A-exciton a WS2, da photoexcited ramukan sauri canjawa wuri a cikin graphene Layer yayin da photoexcited electrons kasance a cikin WS2 Layer. Sakamakon cajin da aka ware na wucin gadi an gano yana da tsawon rayuwar ~ 1 ps. Muna danganta abubuwan da muka gano ga bambance-bambance a cikin sararin lokaci na watsawa ta hanyar daidaitawar dangi na WS2 da makada graphene kamar yadda babban ARPES ya bayyana. A haɗe tare da zugawar gani-zaɓi, binciken WS2/graphene heterostructure na iya samar da dandamali don ingantaccen allurar jujjuyawar gani a cikin graphene.
Samun kayan abu da yawa daban-daban sun buɗe yiwuwar ƙirƙirar wani sabon abu na heterostratores tare da sabbin ayyuka masu amfani da kuma tasirin da suka dace da juna (1-3). Tabbatar da ƙa'idodin ƙa'idodi don aikace-aikacen gaba a fagen lantarki da optoelectronics an gano su (4-6).
Anan, mun mai da hankali kan tsarin heterostructures na epitaxial van der Waals wanda ya ƙunshi monolayer WS2, wani semiconductor mai rata kai tsaye tare da ƙaƙƙarfan haɗaɗɗiyar jujjuyawar juzu'i da rarrabuwa mai girma na tsarin band saboda karyewar juzu'i (7), da monolayer graphene, semimetal. tare da tsarin bandeji na conical da matsanancin motsi mai ɗaukar nauyi (8), wanda aka girma akan SiC mai ƙarewar hydrogen (0001). Alamu na farko don canja wurin cajin ultrafast (9-15) da kusanci-induced spin-orbit hade effects (16-18) sa WS2 / graphene da makamantansu heterostructures alƙawarin 'yan takara na gaba optoelectronic (19) da optospintronic (20) aikace-aikace.
Mun tashi don bayyana hanyoyin shakatawa na nau'i-nau'i-nau'i-nau'i-nau'i-nau'i na lantarki a cikin WS2/graphene tare da lokaci- da kusurwa-resolution photoemission spectroscopy (tr-ARPES). Don wannan dalili, muna sha'awar heterostructure tare da 2-eV famfo bugun jini resonant zuwa A-exciton a cikin WS2 (21, 12) da kuma fitar da photoelectrons tare da na biyu lokaci-jinkiri bugun bugun jini a 26-eV photon makamashi. Muna ƙayyade makamashin motsi da kusurwar fitarwa na photoelectrons tare da mai nazarin hemispherical a matsayin aikin jinkirin famfo-bincike don samun damar yin amfani da kuzari-, makamashi-, da matakan da aka warware na tsawon lokaci. Ƙarfin makamashi da ƙudurin lokaci shine 240 meV da 200 fs, bi da bi.
Sakamakonmu yana ba da shaida kai tsaye don canja wurin cajin ultrafast tsakanin yadudduka masu alaƙa da epitaxially, yana tabbatar da alamun farko dangane da duk dabarun gani a cikin nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan da hannu tare da daidaitawar azimuthal na yadudduka (9-15). Bugu da kari, muna nuna cewa wannan canjin cajin yana da asymmetric sosai. Ma'aunin mu yana bayyana yanayin wucin gadi wanda ba a lura da shi ba tare da ramukan lantarki da ramukan da ke cikin WS2 da graphene Layer, bi da bi, wanda ke rayuwa don ~ 1 ps. Muna fassara abubuwan da muka gano dangane da bambance-bambance a cikin watsawa lokaci sarari don lantarki da canja wurin ramukan da aka haifar ta hanyar daidaitawar dangi na WS2 da maƙallan graphene kamar yadda babban ƙudurin ARPES ya bayyana. Haɗe-haɗe tare da zumuwar gani-da-kwari-zaɓi (22-25) WS2/ graphene heterostructures na iya samar da sabon dandamali don ingantacciyar allurar jujjuyawar gani a cikin graphene.
Hoto 1A yana nuna ma'aunin ARPES mai girma da aka samu tare da fitilar helium na tsarin band tare da ΓK-direction na epitaxial WS2 / graphene heterostructure. An samo majin Dirac a matsayin rami-doped tare da wurin Dirac wanda yake ∼0.3 eV sama da ma'aunin sinadarai. An samo saman rukunin valence WS2 mai jujjuya-tsalle-tsalle-tsalle-tsalle-tsalle-tsalle-tsalle-tsalle-tsalle-tsalle-tsalle-tsalle-tsare-WS2 valence band shine ~1.2 eV a kasa da ma'auni mai yuwuwar sinadaran.
(A) Ma'auni na photocurrent wanda aka auna tare da jagorar ΓK tare da fitilar helium mara nauyi. (B) Photocurrent don mummunan jinkirin famfo-binciken da aka auna tare da p-polarized matsananci ultraviolet bugun jini a 26-eV photon makamashi. Layukan launin toka da ja da aka lalata suna nuna matsayi na bayanan martaba na layi da aka yi amfani da su don cire matsayi mafi girma na wucin gadi a cikin hoto. da 2 mJ/cm2. Ana nuna riba da asarar photoelectrons a cikin ja da shuɗi, bi da bi. Akwatunan suna nuna yankin haɗin kai don alamun binciken famfo da aka nuna a hoto 3.
Hoto 1B yana nuna hoton tr-ARPES na tsarin band kusa da WS2 da graphene K-points wanda aka auna tare da 100-fs matsananciyar ultraviolet bugun jini a 26-eV photon makamashi a mummunan jinkirin famfo-bincike kafin zuwan bugun bugun famfo. Anan, ba a warware rarrabuwar kawuna ba saboda lalacewar samfuri da kasancewar bugun bugun 2-eV wanda ke haifar da faɗaɗa cajin sararin samaniya na fasalin fasalin. Hoto na 1C yana nuna canje-canjen da aka haifar da famfo na hoto game da Fig. 1B a jinkirin famfo-bincike na 200 fs inda siginar famfo-bincike ya kai iyakarsa. Launuka ja da shuɗi suna nuna riba da asarar photoelectrons, bi da bi.
Don yin nazarin wannan arziƙi mai ƙarfi daki-daki, da farko mun ƙididdige matsayi kololuwa na WS2 valence band da graphene π-band tare da layukan dashe a cikin siffa 1B kamar yadda aka yi bayani dalla-dalla a cikin Ƙarin Materials. Mun gano cewa WS2 valence band yana motsawa ta 90 meV (Fig. 2A) kuma graphene π-band yana canzawa ta 50 meV (Fig. 2B). Tsawon rayuwar waɗannan canje-canje ana samunsa shine 1.2 ± 0.1 ps don valence band na WS2 da 1.7 ± 0.3 ps don graphene π-band. Waɗannan kololuwar sauye-sauye suna ba da shaidar farko na cajin wucin gadi na yadudduka biyu, inda ƙarin cajin tabbatacce (mara kyau) yana ƙaruwa (rage) ƙarfin dauri na jihohin lantarki. Lura cewa haɓakawa na WS2 valence band yana da alhakin fitaccen siginar famfo-bincike a cikin yankin da akwatin baƙar fata ke alama a cikin siffa 1C.
Canji a cikin kololuwar matsayi na WS2 valence band (A) da graphene π-band (B) azaman aikin jinkirin famfo-bincike tare da madaidaicin madaidaicin (layi mai kauri). Rayuwar rayuwar canjin WS2 a cikin (A) shine 1.2 ± 0.1 ps. Rayuwar rayuwar motsin graphene a (B) shine 1.7 ± 0.3 ps.
Na gaba, muna haɗa siginar famfo-bincike akan wuraren da aka nuna ta kwalaye masu launi a cikin siffa 1C kuma muna yin ƙididdige ƙididdiga da aka samu a matsayin aikin jinkirin famfo-bincike a cikin hoto. masu ɗaukar hoto masu farin ciki kusa da kasan rukunin gudanarwa na Layer WS2 tare da tsawon rayuwar 1.1 ± 0.1 ps da aka samu daga madaidaicin madaidaici zuwa bayanan (duba Ƙarin Kayayyakin).
Hanyoyin bincike na famfo a matsayin aikin jinkirin da aka samu ta hanyar haɗawa da hotuna a kan yankin da aka nuna ta kwalaye a cikin siffa 1C. Layukan kauri sun yi daidai da bayanan. Curve (1) Yawan jigilar jigilar kayayyaki a cikin rukunin gudanarwa na WS2. Lanƙwasa (2) Siginar bincike-tump na π-band na graphene sama da ma'aunin sinadari. Lanƙwasa (3) Siginar bincike-tump na π-band na graphene a ƙasa da ma'aunin sinadari. Curve (4) siginar binciken famfo-net a cikin valence band na WS2. Ana samun lokacin rayuwa shine 1.2 ± 0.1 ps a cikin (1), 180 ± 20 fs (riba) da ~ 2 ps (asarar) a cikin (2), da 1.8 ± 0.2 ps a (3).
A cikin lanƙwasa 2 da 3 na siffa 3, muna nuna siginar famfo-bincike na graphene π-band. Mun gano cewa ribar electrons sama da ma'aunin sinadarai ma'auni (curve 2 a cikin Fig. 3) yana da ɗan gajeren rayuwa (180 ± 20 fs) idan aka kwatanta da asarar electrons a ƙasa da ma'auni na sinadarai (1.8 ± 0.2 ps a cikin kwana 3). Hoto 3). Bugu da ari, an samo asali na farko na photocurrent a cikin layi na 2 na siffa 3 don juya zuwa hasara a t = 400 fs tare da rayuwar ~ 2 ps. Ana samun asymmetry tsakanin riba da asara ba ya nan a cikin siginar famfo-bincike na graphene monolayer da ba a buɗe ba (duba fig. S5 a cikin ƙarin Kayayyakin), yana nuna cewa asymmetry sakamakon haɗaɗɗiyar tsaka-tsaki a cikin WS2/graphene heterostructure. Duban samun ɗan gajeren lokaci da asarar dogon lokaci sama da ƙasa da ma'auni mai yuwuwar sinadarai, bi da bi, yana nuna cewa ana cire electrons da kyau daga layin graphene a lokacin da ake yin hoto na heterostructure. A sakamakon haka, graphene Layer ya zama tabbatacce cajin, wanda ya dace da karuwa a dauri makamashi na π-band samu a cikin Fig. 2B. Sauƙaƙe na π-band yana kawar da wutsiya mai ƙarfi na ma'auni Fermi-Dirac rarraba daga sama da ma'auni na sinadarai, wanda wani ɓangare ya bayyana canjin alamar siginar famfo-bincike a cikin layi na 2 na Fig. 3. Za mu nuna a ƙasa cewa wannan tasirin yana ƙara haɓaka ta hanyar asarar electrons na wucin gadi a cikin π-band.
Wannan yanayin yana da goyan bayan siginar famfo-binciken net na WS2 valence band a cikin lanƙwasa 4 na siffa 3. An samo waɗannan bayanan ta hanyar haɗa ƙididdiga akan yankin da akwatin baƙar fata ya ba a cikin siffa 1B wanda ke ɗaukar electrons photoemitted daga band valence a duk jinkirin famfo-bincike. A cikin sandunan kuskuren gwaji, ba mu sami wata alama don kasancewar ramuka a cikin valence band na WS2 don kowane jinkirin binciken famfo ba. Wannan yana nuna cewa, bayan daukar hoto, ana cika waɗannan ramukan cikin sauri akan ɗan gajeren lokaci idan aka kwatanta da ƙudurinmu na ɗan lokaci.
Don samar da hujja ta ƙarshe don hasashe na rabuwar cajin ultrafast a cikin WS2/graphene heterostructure, mun ƙayyade adadin ramukan da aka canjawa wuri zuwa layin graphene kamar yadda aka bayyana dalla-dalla a cikin Kayayyakin Kari. A takaice, rarrabawar lantarki na wucin gadi na π-band an saka shi tare da rarraba Fermi-Dirac. Sannan an ƙididdige adadin ramukan daga ƙimar da aka samu don yuwuwar sinadarai na wucin gadi da zafin lantarki. An nuna sakamakon a cikin siffa 4. Mun gano cewa jimlar adadin ~ 5 × 1012 ramuka / cm2 ana canjawa wuri daga WS2 zuwa graphene tare da rayuwa mai mahimmanci na 1.5 ± 0.2 ps.
Canjin adadin ramuka a cikin π-band a matsayin aikin jinkirin famfo-bincike tare da madaidaicin juzu'i yana samar da tsawon rayuwa na 1.5 ± 0.2 ps.
Daga binciken a cikin Fig. 2 zuwa 4, hoton da ke biyo baya don canja wurin cajin ultrafast a cikin WS2/graphene heterostructure ya fito (Fig. 5). Photoexcitation na WS2/graphene heterostructure a 2 eV rinjaye mamaye A-exciton a WS2 (Fig. 5A). Ƙarin abubuwan motsa jiki na lantarki a duk faɗin Dirac a cikin graphene da kuma tsakanin WS2 da maƙallan graphene suna da ƙarfi da ƙarfi amma ba su da inganci. Ramukan hotuna masu ban sha'awa a cikin valence band na WS2 ana sake cika su ta hanyar electrons waɗanda suka samo asali daga graphene π-band akan gajeriyar sikelin lokaci idan aka kwatanta da ƙudurinmu na ɗan lokaci (Fig. 5A). Electrons masu jin daɗi a cikin rukunin gudanarwa na WS2 suna da tsawon rayuwa na ~ 1 ps (Fig. 5B). Koyaya, yana ɗaukar ~ 2 ps don sake cika ramukan da ke cikin graphene π-band (Fig. 5B). Wannan yana nuna cewa, baya ga canja wurin wutar lantarki kai tsaye tsakanin WS2 conduction band da graphene π-band, ƙarin hanyoyin shakatawa—yiwuwa ta jihohin lahani (26)—yana buƙatar a yi la’akari da su don fahimtar cikakken kuzari.
(A) Photoexcitation a resonance zuwa WS2 A-exciton a 2 eV injects electrons a cikin conduction band na WS2. Madaidaitan ramukan da ke cikin valence band na WS2 ana sake cika su nan take ta hanyar lantarki daga graphene π-band. (B) Masu ɗaukar hoto masu farin ciki a cikin rukunin gudanarwa na WS2 suna da tsawon rayuwa na ~ 1 ps. Ramukan da ke cikin graphene π-band suna rayuwa don ~ 2 ps, yana nuna mahimmancin ƙarin tashoshi masu watsawa da aka nuna ta kibau masu tsinke. Layukan baƙar fata a cikin (A) da (B) suna nuna sauye-sauyen bandeji da canje-canje a yuwuwar sinadarai. (C) A cikin yanayin wucin gadi, WS2 Layer ana cajin mara kyau yayin da Layer graphene yana da inganci. Don zaɓen zumuɗi tare da haske mai madauwari mai da'ira, ɗimbin lantarki masu ɗaukar hoto a cikin WS2 da ramukan da suka dace a cikin graphene ana tsammanin za su nuna kishiyar polarization.
A cikin yanayin wucin gadi, na'urorin lantarki masu ɗaukar hoto suna zaune a cikin rukunin gudanarwa na WS2 yayin da ramukan hoto masu ban sha'awa suna cikin π-band na graphene (Fig. 5C). Wannan yana nufin cewa WS2 Layer yana da caji mara kyau kuma ana cajin Layer na graphene da kyau. Wannan asusun don sauye-sauyen kololuwa na wucin gadi (Fig. 2), asymmetry na siginar famfo-bincike na graphene (curves 2 da 3 na siffa 3), rashin ramuka a cikin valence band na WS2 (curve 4 Fig. 3) , da kuma ƙarin ramuka a cikin graphene π-band (Fig. 4). Rayuwar wannan yanayin da aka raba caji shine ~ 1 ps (kwana 1 Fig. 3).
An lura da irin wannan jahohin wucin gadi da aka ware a cikin hanyoyin van der Waals heterostructures da aka yi daga na'urori masu rahusa kai tsaye guda biyu tare da daidaita nau'in band II da bandgap mai tsauri (27-32). Bayan photoexcitation, da electrons da ramukan aka samu da sauri matsawa zuwa kasa na conduction band kuma zuwa saman valence band, bi da bi, wanda aka located a cikin daban-daban yadudduka na heterostructure (27-32).
A cikin yanayin WS2/graphene heterostructure, wurin da ya fi dacewa da kuzari ga duka electrons da ramuka shine a matakin Fermi a cikin layin graphene na ƙarfe. Saboda haka, mutum zai yi tsammanin cewa duka electrons da ramuka suna canzawa cikin sauri zuwa graphene π-band. Koyaya, ma'aunin mu yana nuna a sarari cewa canja wurin rami (<200 fs) ya fi inganci fiye da canja wurin lantarki (~ 1 ps). Mun dangana wannan ga dangi mai kuzari na WS2 da maƙallan graphene kamar yadda aka bayyana a cikin siffa 1A wanda ke ba da adadi mafi girma na jihohi na ƙarshe don canja wurin rami idan aka kwatanta da canja wurin lantarki kamar yadda kwanan nan ake tsammani (14, 15). A halin yanzu, ana ɗaukan ~ 2 eV WS2 bandgap, graphene Dirac point da ma'auni na sinadarai suna samuwa ~ 0.5 da ~ 0.2 eV sama da tsakiyar bandgap na WS2, bi da bi, karya alamar ramukan lantarki. Mun gano cewa adadin da ake samu na ƙarshe don canja wurin rami ya ninka sau 6 girma fiye da na canja wurin lantarki (duba Ƙarin Kayayyakin), shi ya sa ake sa ran canja wurin rami zai yi sauri fiye da canja wurin lantarki.
Cikakken hoto na ultrafast asymmetric cajin da aka lura ya kamata, duk da haka, kuma yayi la'akari da haɗuwa tsakanin orbitals wanda ya ƙunshi aikin A-exciton wave a cikin WS2 da graphene π-band, bi da bi, daban-daban electron-electron da electron-phonon watsawa. tashoshi ciki har da ƙuntatawa da aka sanya ta hanzari, makamashi, spine, da kuma pseudospin kiyayewa, tasirin oscillations na plasma. (33), da kuma rawar yuwuwar ɓacin rai na motsin murya mai daidaituwa wanda zai iya daidaita canjin caji (34, 35). Hakanan, ana iya yin hasashe ko yanayin canja wurin cajin da aka lura ya ƙunshi abubuwan canja wurin caji ko nau'i-nau'i na ramin lantarki kyauta (duba Ƙarin Kayayyakin). Ana buƙatar ƙarin bincike na ka'idar da ya wuce iyakar wannan takarda don bayyana waɗannan batutuwa.
A taƙaice, mun yi amfani da tr-ARPES don nazarin ultrafast interlayer caja a cikin wani epitaxial WS2/graphene heterostructure. Mun gano cewa, lokacin da farin ciki a resonance zuwa A-exciton na WS2 a 2 eV, da photoexcited ramukan sauri canjawa wuri a cikin graphene Layer yayin da photoexcited electrons kasance a cikin WS2 Layer. Mun dangana wannan ga gaskiyar cewa adadin jihohin ƙarshe don canja wurin ramuka ya fi girma fiye da canja wurin lantarki. An gano tsawon rayuwar cajin da aka raba na wucin gadi ya kasance ~ 1 ps. A haɗe tare da zugawar gani na zaɓe ta amfani da hasken da'irar madauwari (22-25), canjin cajin da aka lura yana iya kasancewa tare da canja wurin juyi. A wannan yanayin, ana iya amfani da WS2/graphene heterostructure da aka bincika don ingantaccen allurar jujjuyawar gani a cikin graphene wanda ke haifar da na'urorin optospintronic na zamani.
Samfuran graphene an haɓaka su akan wafers na 6H-SiC (0001) na kasuwanci daga SiCrystal GmbH. Wafers ɗin N-doped sun kasance akan axis tare da kuskuren ƙasa 0.5°. Tushen SiC ɗin ya kasance hydrogen-etched don cire karce da samun filaye na yau da kullun. Sa'an nan kuma aka zana sifili mai tsafta da atomically Si-terminated ta hanyar shafe samfurin a yanayin Ar a 1300°C na mintuna 8 (36). Ta wannan hanyar, mun sami Layer carbon guda ɗaya inda kowane atom ɗin carbon na uku ya samar da haɗin kai ga ma'aunin SiC (37). Daga nan sai aka juya wannan Layer zuwa gabaɗaya sp2-hybridized quasi free-standing hole-doped graphene via hydrogen intercalation (38). Ana kiran waɗannan samfuran a matsayin graphene / H-SiC (0001). Dukkanin tsarin an gudanar da shi a cikin ɗakin girma na Black Magic na kasuwanci daga Aixtron. An gudanar da haɓakar WS2 a cikin ma'auni mai zafi mai zafi ta hanyar ƙananan ƙwayar tururi mai zafi (39, 40) ta amfani da WO3 da S powders tare da yawan adadin 1: 100 a matsayin precursors. An ajiye foda na WO3 da S a 900 da 200 ° C, bi da bi. An sanya foda WO3 kusa da substrate. An yi amfani da Argon azaman iskar gas tare da kwararar 8 sccm. An kiyaye matsa lamba a cikin reactor a 0.5 mbar. Samfurori an siffanta su da ƙananan ƙananan na'urorin lantarki na biyu, microscopy ƙarfin atomic, Raman, da na'urar hangen nesa ta photoluminescence, da ƙarancin wutar lantarki. Waɗannan ma'aunai sun bayyana nau'o'in WS2 guda-crystalline daban-daban inda ko dai ΓK- ko ΓK'-direction ya daidaita tare da ΓK-direction na graphene Layer. Tsawon gefen yanki ya bambanta tsakanin 300 da 700 nm, kuma an kiyasta jimillar ɗaukar hoto na WS2 zuwa ~40%, wanda ya dace da nazarin ARPES.
An yi gwaje-gwajen ARPES na tsaye tare da na'urar nazari na hemispherical (SPECS PHOIBOS 150) ta amfani da tsarin gano na'urar da aka haɗe-haɗe-haɗe don gano ƙarfin lantarki da kuzari mai girma biyu. Unpolarized, monochromatic He Iα radiation (21.2 eV) na wani babban-fifi Ya fitar da tushen (VG Scienta VUV5000) da aka yi amfani da duk photoemission gwaje-gwaje. Ƙimar makamashi da ƙuduri a cikin gwaje-gwajenmu sun fi 30 meV da 0.3 ° (daidai da 0.01 Å-1), bi da bi. An gudanar da duk gwaje-gwaje a cikin zafin jiki. ARPES wata fasaha ce ta musamman mai saurin kamuwa da ita. Don fitar da photoelectrons daga duka WS2 da graphene Layer, an yi amfani da samfurori tare da cikakken ɗaukar hoto na WS2 na ~ 40%.
Saitin tr-ARPES ya dogara ne akan 1-kHz Titanium: Sapphire amplifier (Coherent Legend Elite Duo). An yi amfani da 2mJ na ƙarfin fitarwa don haɓakar haɓakar haɗin kai a cikin argon. Sakamakon matsananciyar hasken ultraviolet ya wuce ta hanyar monochromator grating yana samar da bugun jini na 100-fs a makamashin photon 26-eV. An aika 8mJ na ƙarfin fitarwa na amplifier zuwa cikin na'urar ƙararrawa na gani (HE-TOPAS daga Canjin Haske). Siginar siginar a 1-eV makamashin photon an ninka mitar-biyu a cikin beta barium borate crystal don samun ƙwararrun famfo na 2-eV. An yi ma'aunin tr-ARPES tare da na'urar nazari mai zurfi (SPECS PHOIBOS 100). Gabaɗayan ƙarfin kuzari da ƙudurin ɗan lokaci shine 240 meV da 200 fs, bi da bi.
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Daga Sven Aeschlimann, Antonio Rossi, Mariana Chávez-Cervantes, Razvan Krause, Benito Arnoldi, Benjamin Stadtmüller, Martin Aeschlimann, Stiven Forti, Filippo Fabbri, Camilla Coletti, Isabella Gierz
Muna bayyana rabuwar cajin ultrafast a cikin tsarin WS2/graphene heterostructure mai yiwuwa yana ba da damar allurar jujjuyawar gani a cikin graphene.
Daga Sven Aeschlimann, Antonio Rossi, Mariana Chávez-Cervantes, Razvan Krause, Benito Arnoldi, Benjamin Stadtmüller, Martin Aeschlimann, Stiven Forti, Filippo Fabbri, Camilla Coletti, Isabella Gierz
Muna bayyana rabuwar cajin ultrafast a cikin tsarin WS2/graphene heterostructure mai yiwuwa yana ba da damar allurar jujjuyawar gani a cikin graphene.
© 2020 Ƙungiyar Amirka don Ci gaban Kimiyya. An kiyaye duk haƙƙoƙi. AAAS abokin tarayya ne na HINARI, AGORA, OARE, CHORUS, CLOCKSS, CrossRef da COUNTER. Ci gaban Kimiyya ISSN 2375-2548.
Lokacin aikawa: Mayu-25-2020