Horumarka tignoolajiyada isha iftiinka ultraviolet ee xad dhaafka ah

Horumarka ultraviolet darantignoolajiyada isha iftiinka

Sanadihii la soo dhaafay, ilaha harmonic sare ee ultraviolet ayaa soo jiitay dareenka ballaaran ee duurka dhaqdhaqaaqa elektaroonigga ah sababtoo ah isku xirnaantooda xooggan, muddada garaaca garaaca gaaban iyo tamarta sare ee photon, waxaana loo isticmaalay daraasado muuqaal iyo muuqaal ah oo kala duwan. Iyadoo horumarinta tignoolajiyada, taniil iftiin lehwaxay u koraysaa dhanka soo noqnoqoshada sare ee soo noqnoqda, qulqulka photon-ka oo sareeya, tamarta photon sare iyo ballaca garaaca garaaca oo gaaban. Horusocodkani kaliya ma wanaajiyo xallinta cabbiraadda ilaha iftiinka ultraviolet ee aadka u daran, laakiin sidoo kale waxay bixisaa fursado cusub ee isbeddellada horumarinta tignoolajiyada mustaqbalka. Sidaa darteed, daraasadda qoto-dheer iyo fahamka soo noqnoqoshada sare ee soo noqnoqda isha iftiinka ultraviolet ee xad dhaafka ah ayaa muhiimad weyn u leh hanashada iyo adeegsiga tignoolajiyada gees-goynta.

Qiyaasta spectroscopy elektarooniga ah ee miisaanka femtosecond iyo attosecond, tirada dhacdooyinka lagu cabiro hal laydh inta badan kuma filna, taasoo ka dhigaysa ilo iftiin ah oo hooseeya oo aan ku filnayn si loo helo tirakoobyo la isku halayn karo. Isla mar ahaantaana, isha iftiinka leh qulqulka photon-ka hooseeya waxay yareyn doontaa saamiga calaamad-ilaa-sanqa ee sawir-qaadista microscopic inta lagu jiro wakhtiga xaddidan ee soo-gaadhista. Iyada oo loo marayo sahaminta iyo tijaabooyinka joogtada ah, cilmi-baarayaashu waxay sameeyeen horumarin badan oo ku saabsan hagaajinta wax-soo-saarka iyo qaabaynta gudbinta ee soo noqnoqda sare ee iftiinka ultraviolet ee xad dhaafka ah. Tiknoolajiyada falanqaynta muuqaalka sare leh oo ay weheliso soo noqnoqoshada sare ee soo noqnoqda isha iftiinka ultraviolet ee xad dhaafka ah ayaa loo adeegsaday si loo gaaro cabbirka saxda ah ee saxda ah ee qaab dhismeedka walxaha iyo habka firfircoonida elektiroonigga ah.

Codsiyada ilaha iftiinka ultraviolet ee aadka u daran, sida cabbirada elektaroonigga ah ee xaglaha la xalliyo (ARPES), waxay u baahan yihiin iftiin aad u daran oo ultraviolet ah si loo iftiimiyo saamiga. Elektaroonada ku yaal dusha muunada waxay ku faraxsan yihiin xaalada joogtada ah ee iftiinka ultraviolet ee aadka u daran, tamarta kinetic iyo xagasha qiiqa ee sawir-qaadayaasha waxaa ku jira macluumaadka qaab dhismeedka band ee muunada. Falanqeeyaha elektarooniga ah ee leh shaqada xallinta xagasha wuxuu helayaa sawir-qaadayaasha shucaaca ah wuxuuna helayaa qaab-dhismeedka kooxda ee u dhow kooxda valence ee muunada. Soo noqnoqoshada hooseeya ee ilayska ultraviolet ee xad dhaafka ah, sababtoo ah hal garaaca wadnaha ayaa ka kooban tiro badan oo photons ah, waxay ku farxi doontaa tiro badan oo photoelectrons ah oogada muunada waqti gaaban gudaheed, isdhexgalka Coulomb wuxuu keeni doonaa ballaarin halis ah qaybinta. tamarta tamarta tamarta ee loo yaqaan 'photoelectron kinetic energy', oo loo yaqaan 'space charge effect'. Si loo yareeyo saamaynta saamaynta lacag-dhaafka booska, waxaa lagama maarmaan ah in la yareeyo photoelectrons ku jira garaaca wadnaha kasta iyadoo la ilaalinayo qulqulka photon joogto ah, sidaas darteed waa lagama maarmaan in la wadoleysarkaoo leh soo noqnoqosho sarreeya si loo soo saaro isha iftiinka ultraviolet ee xad dhaafka ah oo leh soo noqnoqoshada sare.

Tignoolajiyada daloolka ee la xoojiyey ee resonance waxa ay garwaaqsataa soo saarista habraaca nidaamka sare leh ee soo noqnoqoshada MHz
Si loo helo ilayska ultraviolet-ka xad dhaafka ah ee leh soo noqnoqda ilaa 60 MHz, kooxda Jones ee Jaamacadda British Columbia ee Boqortooyada Midowday waxay sameeyeen jiil iswaafajin oo heer sare ah oo ku yaal daloolka kor u qaadista resonance femtosecond (fsEC) si loo gaaro waxqabad la taaban karo. Ilaha iftiinka ultraviolet ee xad dhaafka ah oo ku dabaqay tijaabooyinka elektaroonigga ah ee la xaliyay ee xagal-xallinta ah (Tr-ARPES). Isha iftiinka ayaa awood u leh in ay gudbiso qulqulka photon ee in ka badan 1011 nambarada photon ilbiriqsi kasta oo leh hal harmonic oo ah celceliska celceliska 60 MHz ee qiyaasta tamarta ee 8 ilaa 40 eV. Waxay isticmaaleen nidaamka laser fiber ytterbium-doped sidii il abuurka fsEC, iyo sifooyinka garaaca garaaca la xakameeyey iyada oo loo marayo qaabaynta nidaamka laser la habeeyey si loo yareeyo buuqa baqshadda sideyaasha (fCEO) loona ilaaliyo sifooyinka garaaca garaaca garaaca garaaca garaaca wadnaha dhamaadka silsiladda amplifier. Si loo gaaro kor u qaadida dhawaaqa xasilloon ee gudaha fsEC, waxay isticmaalaan seddexda koontaroolada kontoroolka servo si loo xakameeyo jawaab celinta, taasoo keentay xasilooni firfircoon laba darajo oo xoriyad ah: wakhtiga safarka wareega ee baaskiil wadida gudaha fsEC waxay u dhigantaa xilliga garaaca garaaca laysarka, iyo isbedelka wajiga ee sidaha garoonka korantada marka la eego baqshadda garaaca wadnaha (tusaale ahaan, wejiga baqshadda side, ϕCEO).

Isticmaalka gaaska krypton sida gaaska shaqada, kooxda cilmi-baarista waxay ku guuleysteen jiilka harmonics-ka sare ee fsEC. Waxay sameeyeen qiyaasaha Tr-ARPES ee garaafyada waxayna arkeen kulayl degdeg ah iyo dib u habeyn tartiib tartiib ah ee dadka elektaroonigga ah ee aan ku faraxsanayn, iyo sidoo kale dhaqdhaqaaqyada aan kuleylka tooska ahayn ee u dhow heerka Fermi ee ka sarreeya 0.6 eV. Isha iftiinku waxay bixisaa qalab muhiim ah oo lagu baranayo qaabka elektiroonigga ah ee qalabka adag. Si kastaba ha ahaatee, jiilka hab-dhismeedka sare ee fsEC wuxuu leeyahay shuruudo aad u sarreeya oo loogu talagalay milicsiga, magdhowga kala firdhisan, hagaajinta wanaagsan ee dhererka godka iyo qufulka isku-dhafka, taas oo si weyn u saameyn doonta kobcinta badan ee kor u kaca ee kor u kaca. Isla mar ahaantaana, jawaabta wajiga aan tooska ahayn ee balasmaha ee barta xudunta u ah daloolka ayaa sidoo kale ah caqabad. Sidaa darteed, wakhtigan xaadirka ah, ilayska noocan ahi ma noqon ultraviolet-ka xad dhaafka ah ee caadiga ahilayska harmonic sare.