Umgaqo oqhelekileyo othi “kunamandla ngakumbi” kudala umiselwa kumacandelo amaninzi oluntu, kuquka inzululwazi nobugcisa. Nangona kunjalo, kwizinto zanamhlanje, ukuphunyezwa okusebenzayo kwezwi elithi "encinci, kodwa linamandla" liba lixhaphake ngakumbi. Oku kubonakaliswa kwiikhomputha, eziye zathatha igumbi lonke, kodwa ngoku zilungele entendeni yomntwana, kunye ne-accelerators ehlawulweyo. Ewe, khumbula iLarge Hadron Collider (LHC), enemilinganiselo enomtsalane (26 m ubude) iboniswe ngokoqobo egameni layo? Ngoko ke, le nto sele iyinto edlulileyo ngokwezenzululwazi ezivela kwi-DESY, abaye baphuhlisa inguqu encinci ye-accelerator, engekho ngaphantsi kwentsebenzo kwi-predecessor yayo epheleleyo. Ngaphezu koko, i-accelerator encinci ide ibeke irekhodi elitsha lehlabathi phakathi kwee-accelerator ze-terahertz, iphinda kabini amandla ee-electron ezifakwe ngaphakathi. Saphuhliswa njani isikhawulezisi esincinci, yeyiphi imigaqo esisiseko yokusebenza kwaso, kwaye imifuniselo ebonakalayo ibonise ntoni? Ingxelo yeqela lophando iya kusinceda sifumane malunga noku. Hamba.
Isiseko sophando
NgokukaDongfang Zhang kunye noogxa bakhe eDESY (iGerman Electron Synchrotron), ephuhlise i-mini-accelerator, imithombo ye-electron ekhawulezayo idlala indima ebaluleke kakhulu kubomi boluntu lwanamhlanje. Uninzi lwazo lubonakala kumayeza, uphuhliso lwe-elektroniki kunye nophando lwesayensi. Eyona ngxaki inkulu ngee-accelerators zangoku zisebenzisa ii-oscillator zerediyo lixabiso labo eliphezulu, iziseko ezingundoqo ezintsonkothileyo, kunye nokusetyenziswa kwamandla okuchukumisayo. Kwaye ezo ntsilelo zinciphisa kakhulu ukufumaneka kwezobuchwephesha kuluhlu olubanzi lwabasebenzisi.
Ezi ngxaki zicacileyo ziyinkuthazo enkulu yokuphuhlisa izixhobo ezinobungakanani kunye nokusetyenziswa kwamandla kungayi kubangela uloyiko.
Phakathi kwezinto ezintsha ezizalanayo kolu shishino zii-terahertz accelerators, ezinenani “leenzuzo”:
- Kulindeleke ukuba amaza amafutshane kunye neepulses ezimfutshane zemitha ye-terahertz ziya kwandisa kakhulu umda yoyisakala*, ebangelwa yintsimi, eya kwandisa i-acceleration gradients;
Ukophuka kombane* - ukunyuka okubukhali kumandla angoku xa i-voltage engaphezulu ibaluleke kakhulu isetyenziswa.
- ubukho beendlela ezisebenzayo zokuvelisa imitha ye-terahertz ye-high-field ivumela ulungelelwaniso lwangaphakathi phakathi kwee-electron kunye nemimandla yokuvuselela;
- Iindlela zeClassical zingasetyenziselwa ukudala izixhobo ezinjalo, kodwa iindleko zabo, ixesha lokuvelisa kunye nobukhulu ziya kuncitshiswa kakhulu.
Izazinzulu zikholelwa ukuba i-millimeter-scale terahertz accelerator yi-compromise phakathi kwee-accelerators eziqhelekileyo ezikhoyo ngoku kunye ne-micro-accelerators eziphuhliswayo, kodwa zineziphene ezininzi ngenxa yemilinganiselo yazo encinci kakhulu.
Abaphandi abakhanyeli ukuba itekhnoloji yokukhawulezisa i-terahertz sele iphuhliswa ixesha elithile. Nangona kunjalo, ngokoluvo lwabo, kusekho imiba emininzi kule ndawo engakhange ifundwe, ivavanywe okanye iphunyezwe.
Kumsebenzi wabo, esiwuqwalaselayo namhlanje, izazinzulu zibonisa ubuchule be-STEAM (i-accelerator ye-electron ye-terahertz kunye ne-manipulator) - i-terahertz ye-electron accelerator kunye ne-manipulator. I-STEAM ivumela ubude be-electron beam ukuba buncitshiswe kwi-sub-picosecond ubude, ngokubonelela ngolawulo lwe-femtosecond kwisigaba sokukhawuleza.
Kwakunokwenzeka ukufezekisa intsimi yokukhawuleza ye-200 MV / m (MV - megavolt), ekhokelela kwirekhodi ye-terahertz yokukhawuleza> 70 keV (kiloelectronvolt) ukusuka kwi-electron beam edibeneyo kunye namandla angama-55 keV. Ngale ndlela, ii-electron ezikhawulezayo ukuya kwi-125 keV zifunyenwe.
Ubume besixhobo kunye nokuphunyezwa
Inombolo yomfanekiso 1: umzobo wesixhobo esiphantsi kofundo.
Umfanekiso we-1-2: umzobo we-5-layer segmented structure ephuhlisiwe, b - umlinganiselo wokubala ukukhawuleza kunye nolwalathiso lwe-electron yokusabalalisa.
Imiqadi ye-electron (55 keV) yenziwe ukusuka umpu we-electron* kwaye zingeniswa kwi-terahertz STEAM-buncher (i-compressor ye-beam), emva koko badlula kwi-STEAM-linac (isantya somgca*).
Umpu we-electron* — isixhobo sokuvelisa umqa wee-electron wobumbeko olufunekayo kunye namandla.
Isantya somgca* - i-accelerator apho iinqununu ezihlawulisiweyo zidlula kwisakhiwo kanye kuphela, esahlula i-accelerator yomgca ukusuka kwi-cyclic (umzekelo, i-LHC).
Zombini izixhobo ze-STEAM zifumana i-terahertz pulses kwilaser enye ekufutshane ne-infrared (NIR), ekwatshisa ifotocathode yompu we-electron, okukhokelela kungqamaniso lwangaphakathi phakathi kwee-electron kunye neendawo ezikhawulezayo. I-Ultraviolet pulses ye-photoemission kwi-photocathode yenziwa ngezigaba ezimbini ezilandelelanayo GVG* Ubude obusisiseko bokukhanya okukufutshane kwe-infrared. Le nkqubo iguqula i-1020 nm laser pulse kuqala ibe yi-510 nm ize ibe yi-255 nm.
GVG* (i-optical yesibini ye-harmonic generation) yinkqubo yokudibanisa i-photons ye-frequency efanayo ngexesha lokusebenzisana kunye ne-nonlinear material, ekhokelela ekwakhiweni kweefotoni ezintsha eziphindwe kabini amandla kunye nokuphindaphinda, kunye nesiqingatha sobude be-wavelength.
Intsalela yomqadi we-laser ye-NIR yahlulahlulwe yaba yimiqadi emi-4, esetyenziselwa ukuvelisa iipulse ezine ze-terahertz zomjikelo omnye ngokuvelisa iyantlukwano yamaza e-intra-pulse.
Iipulses ezimbini ze-terahertz ke zihanjiswa kwisixhobo ngasinye se-STEAM kusetyenziswa i-symmetrical horn structures eqondisa amandla e-terahertz kummandla wokunxibelelana ngaphesheya kokusasazwa kwe-electron.
Xa ii-electron zingena kwisixhobo ngasinye se-STEAM, zivezwa kumalungu ombane kunye nemagnethi Imikhosi kaLorentz*.
Lorentz force* - amandla apho intsimi ye-electromagnetic isebenza kwisuntswana elihlawulweyo.
Kule meko, intsimi yombane inoxanduva lokukhawuleza kunye nokunciphisa, kwaye intsimi yamagnetic ibangela ukuphambuka kwecala.
Umfanekiso #2
Njengoko sibona kwimifanekiso 2 и 2b, Ngaphakathi kwesixhobo ngasinye se-STEAM, imiqadi ye-terahertz yahlulwe ngokunqamlezileyo ngamacwecwe esinyithi amancinci abe ngamanqanaba ahlukeneyo obunzima obuhlukeneyo, ngalinye lisebenza njenge-waveguide, idlulisela inxalenye yamandla ewonke kummandla wokusebenzisana. Kukho neepleyiti ze-dielectric kwinqanaba ngalinye ukulungelelanisa ixesha lokufika kwe-terahertz waliza ngaphambili* nomphambili wee-electron.
Umphambili wamaza* - indawo apho i-wave ifikelele khona.
Zombini izixhobo ze-STEAM zisebenza kwimodi yombane, oko kukuthi, ngendlela yokunyanzelisa intsimi yombane kunye nokucinezela intsimi yamagnetic embindini wendawo yokunxibelelana.
Kwisixhobo sokuqala, ii-electron zibekwe ixesha ukuba zidlule Ukuwela zero* intsimi ye-terahertz, apho i-gradients zexesha lentsimi yombane zenziwa zandiswa kwaye intsimi yomndilili iyancitshiswa.
Iqanda lokuwela* - indawo apho kungekho ntlupheko.
Olu lungelelwaniso lubangela ukuba umsila we-electron beam ukhawuleze kwaye intloko yayo ihle, okukhokelela ekugxilweni kwe-ballistic longitudinal (2 и 2s).
Kwisixhobo sesibini, ungqamaniso lwemitha ye-electron kunye ne-terahertz imiselwe ukwenzela ukuba umqa we-electron uhlangabezane nomjikelo ombi wentsimi yombane ye-terahertz. Olu qwalaselo lubangela umnatha oqhubekayo wokukhawulezisa (2b и 2d).
I-laser ye-NIR ifana ne-cryogenically cooled Yb: YLF inkqubo, evelisa i-optical pulses ye-1.2 ps ubude kunye ne-50 mJ yamandla kwi-wavelength ye-1020 nm kunye nesantya sokuphindaphinda i-10 Hz. Kwaye i-terahertz pulses ene-central frequency ye-0.29 terahertz (ixesha le-3.44 ps) iveliswa yi-inclined pulse front method.
Ukunika amandla i-STEAM-buncher (i-compressor ye-beam) kuphela i-2 x 50 nJ yamandla e-terahertz yasetyenziswa, kunye ne-STEAM-linac (i-accelerator yomgca) ifuna i-2 x 15 mJ.
Idayamitha yokungena kunye nemingxuma yokuphuma kuzo zombini izixhobo ze-STEAM yi-120 microns.
I-compressor ye-boam yenziwe ngemigangatho emithathu yokuphakama okulinganayo (0 mm), ezixhotywe ngamacwecwe e-silica adibeneyo (ϵr = 225) ubude be-4.41 kunye ne-0.42 mm ukulawula ixesha. Ubude obulinganayo bomaleko wecompressor bubonisa into yokuba akukho kukhawulezisa (2s).
Kodwa kwi-accelerator yomgca ukuphakama sele kuhluke - 0.225, 0.225 kunye ne-0.250 mm (+ iiplate ze-quartz ezidibeneyo 0.42 kunye ne-0.84 mm). Ukunyuka kobude boluhlu kuchaza ukwanda kwesantya see-electron ngexesha lokukhawuleza.
Iingcali zenzululwazi ziqaphela ukuba inani leeleya lijongene ngqo nokusebenza kwesixhobo ngasinye kwezi zimbini. Ukufikelela kumazinga aphezulu okukhawulezisa, umzekelo, kuya kufuna iileya ezingaphezulu kunye nolungelelwaniso lobude olwahlukileyo ukuze kunyuswe unxibelelwano.
Iziphumo zovavanyo olusebenzayo
Okokuqala, abaphandi bakhumbuza ukuba kwii-accelerators zerediyo zemveli, isiphumo sobungakanani bexesha le-electron beam edibeneyo kwiipropathi zombane okhawulezileyo kungenxa yotshintsho kwindawo yombane efunyenwe ngexesha lokusebenzisana kwee-electron ezahlukeneyo ngaphakathi komqadi wokufika. ngamaxesha ahlukeneyo. Ke, kunokulindelwa ukuba amasimi aneemitha eziphakamileyo kunye nemiqadi enexesha elide aya kukhokelela ekusasazweni okukhulu kwamandla. Imiqadi etofelweyo yexesha elide inokukhokelela kumaxabiso aphezulu ukukhutshwa*.
Emittance* -Isithuba sesigaba esithathwe ngumqa okhawulezileyo wamasuntswana ahlawuliweyo.
Kwimeko ye-accelerator ye-terahertz, ixesha lendawo yokuvuselela limalunga namaxesha angama-200 mfutshane. Ngoko ke, uxinzelelo* intsimi exhaswayo iya kuba ngamaxesha angama-10 aphezulu.
Amandla ebala lombane* - isalathisi sentsimi yombane, elingana nomlinganiselo wamandla asetyenziswe kwintlawulo yendawo yokumisa ebekwe kwindawo enikezelweyo kwintsimi ukuya kubukhulu beli ntlawulo.
Ke, kwi-accelerator ye-terahertz, i-gradient yentsimi efunyanwa yi-electron inokuba yimiyalelo emininzi yobukhulu obuphezulu kunesixhobo esiqhelekileyo. Ubungakanani bexesha apho i-curvature yentsimi ibonakala iya kuba ncinane kakhulu. Kulandela oku ukuba ixesha le-electron beam eyaziswayo iya kuba nesiphumo esicacileyo.
Izazinzulu zagqiba ekubeni zivavanye ezi thiyori ngokusebenza. Ukwenza oku, bazisa imiqadi ye-electron yobude obuhlukeneyo, obulawulwa ngokunyanzeliswa kusetyenziswa isixhobo sokuqala se-STEAM (STEAM-buncher).
Umfanekiso #3
Kwimeko apho icompressor yayingaqhagamshelwanga kumthombo wamandla, imiqadi yee-electron (55 keV) enentlawulo ye ~ 1 fC (femtocoulomb) idlule malunga ne-300 mm ukusuka kumpu we-electron ukuya kwisixhobo sokukhawulezisa somgca (STEAM-linac). Ezi electron zinokukhula phantsi kweempembelelo zeendleko zesithuba ukuya kuthi ga kwixesha elingaphezu kwe-1000 fs (femtoseconds).
Ngeli xesha, i-electron beam ithathe malunga ne-60% yesiqingatha se-wavelength yentsimi ekhawulezayo kwi-frequency ye-1,7 ps, okukhokelela kwi-post-acceleration energy spectrum kunye nencopho ye-115 keV kunye nesiqingatha sobubanzi bokusasazwa kwamandla. ngaphezulu kwe-60 keV (3).
Ukuthelekisa ezi ziphumo kunye nezo zilindelekileyo, imeko yokusasazwa kwe-electron ngokusebenzisa i-accelerator yomgca yalinganiswa xa ii-electron zingekho sync kunye (okt, ngaphandle kokuvumelanisa kunye) nelona xesha lifanelekileyo lokutofa. Ubalo lwale meko lubonise ukuba ukonyuka kwamandla e-electron kuxhomekeke kakhulu kwixesha lokutofa, ukuya kuthi ga kwi-subpicosecond time scale (3b). Oko kukuthi, ngolungiselelo olufanelekileyo, i-electron iya kufumana umjikelo opheleleyo wesiqingatha somjikelo wemitha ye-terahertz kwinqanaba ngalinye (3s).
Ukuba ii-electron zifika ngamaxesha ahlukeneyo, zifumana ukukhawulezisa okuncinci kwinqanaba lokuqala, okubangela ukuba bathathe ixesha elide ukuhamba kulo. I-desynchronization ngoko yonyuka kula maleko alandelayo, ibangela ukucotha okungafunwayo (3d).
Ukuze kuncitshiswe umphumo ongalunganga wokwandiswa kwexesha le-electron beam, isixhobo sokuqala se-STEAM sisebenze kwimodi yoxinzelelo. Ubude bexesha lomqa we-electron kwi-linac buphuculwe ukuya kutsho kubuncinci be-~350 fs (isiqingatha sobubanzi) ngokulungelelanisa amandla e-terahertz anikezelwe kwicompressor kunye nokutshintsha i-linac kwimowudi yokuqandusela.4b).
Umfanekiso #4
Ubuncinci bexesha beam bubekwe ngokuhambelana nexesha le-photocathode UV pulse, eyayiyi ~ 600 fs. Umgama phakathi kwecompressor kunye nomtya nawo udlale indima ebalulekileyo, ethintela isantya samandla okuqina. Ngokudibeneyo, la manyathelo enza ukuba i-femtosecond ichaneke kwisigaba sokutofa sesigaba sokukhawulezisa.
Kumfanekiso 4 kunokubonwa ukuba ukusasazeka kwamandla komqadi we-elektroni ocinezelweyo emva kokunyusa isantya kwi-accelerator yomgca kwehla nge ~ amaxesha ama-4 xa kuthelekiswa nengaxinzelelwanga. Ngenxa yokukhawuleza, i-spectrum yamandla ye-beam ecinezelweyo itshintshelwe kumandla aphezulu, ngokungafaniyo ne-beam enganyanzeliswanga. Incopho ye-spectrum yamandla emva kokukhawuleza imalunga ne-115 keV, kwaye umsila ophezulu wamandla ufikelela malunga ne-125 keV.
La manani, ngokwengxelo ethobekileyo yezazinzulu, irekhodi elitsha lokukhawulezisa (ngaphambi kokukhawuleza kwaba yi-70 keV) kuluhlu lwe-terahertz.
Kodwa ukuze kuncitshiswe ukusasazwa kwamandla (4), kufuneka kufikelelwe umqadi omfutshane ngakumbi.
Umfanekiso #5
Kwimeko ye-beam engaxinzelelwanga eyaziswayo, ukuxhomekeka kwe-parabolic yobukhulu be-beam kwi-current ityhila ukuphuma kwe-transverse kwiindlela ezithe tye kunye nezithe nkqo: εx,n = 1.703 mm * mrad kunye ne-εy,n = 1.491 mm * mrad (5).
Ukunyanzeliswa, kwakhona, kuphuculwe ukukhutshwa kwe-transverse ngama-6 amaxesha ukuya ku-εx, n = 0,285 mm * mrad (horizontal) kunye ne-εy,n = 0,246 mm * mrad (ethe nkqo).
Kuyaphawuleka ukuba iqondo lokuncitshiswa kwe-emittance liphantse liphindwe kabini njengeqondo lokunciphisa ubude be-beam, nto leyo engumlinganiselo wokungahambelani kweendlela zokusebenzisana kunye nexesha apho ii-electron zifumana ukugxilwa okunamandla kunye nokunciphisa amandla ombane ngexesha lokukhawuleza (i-acceleration).5b и 5s).
Kumfanekiso 5b Kungabonwa ukuba ii-electron eziveliswe ngexesha elifanelekileyo zifumana isiqingatha somjikelo wokukhawulezisa intsimi yombane. Kodwa ii-electron ezifika ngaphambi okanye emva kwexesha elifanelekileyo zifumana isantya esincinci kunye nokuhla kancinci. Ezo electron ziphela zifumana amandla amancinci, xa sithetha.
Imeko efanayo ibonwa xa utyhileke kwimagnethi. Ii-elektroni ezitofwe ngexesha elifanelekileyo zifumana izixa ezilinganayo zommandla wemagnethi owakhayo kunye nombi. Ukuba ukuqaliswa kwee-electron kwenzeka ngaphambi kwexesha elifanelekileyo, ngoko kwakukho iindawo ezintle kunye nezimbalwa ezimbi. Ukuba ii-electron ziziswa mva kunexesha elilelona lilungileyo, kuya kuba mbalwa okulungileyo nokubi kakhulu (5s). Kwaye ukutenxa okunjalo kukhokelela kwinto yokuba i-electron ingaphambuka ukuya ekhohlo, ekunene, phezulu okanye ezantsi, ngokuxhomekeke kwindawo yayo ngokunxulumene ne-axis, nto leyo ekhokelela ekwandeni kwesantya esinqamlezileyo esihambelana nokugxila okanye ukuchithwa kwe-beam.
Ukuze ufumane ulwazi oluthe kratya malunga nee-nuances zophononongo, ndincoma ukujonga и kuye.
Ipilo
Isishwankathelo, ukusebenza kwe-accelerator kuya kwanda ukuba ixesha le-electron beam liyancitshiswa. Kulo msebenzi, ubude be-beam obunokufezekiswa bukhawulelwe yijometri yofakelo. Kodwa, ngokwethiyori, ixesha lomqadi lingafikelela ngaphantsi kwe-100 fs.
Iingcali zenzululwazi ziphinde ziqaphele ukuba umgangatho we-beam ungaphuculwa ngakumbi ngokunciphisa ukuphakama kwemigangatho kunye nokwandisa inani labo. Nangona kunjalo, le ndlela ayikho ngaphandle kweengxaki, ngokukodwa ukwandisa ubunzima bokuvelisa isixhobo.
Lo msebenzi linqanaba lokuqala lophononongo olunabileyo noluneenkcukacha lwenguqulelo encinci ye-accelerator yomgama. Ngaphandle kwento yokuba uguqulelo oluvavanyiweyo sele lubonisa iziphumo ezigqwesileyo, ezinokuthiwa ngokufanelekileyo ukuphulwa kwerekhodi, kusekho umsebenzi omningi wokwenza.
Enkosi ngokufunda, hlala unomdla kwaye ube neveki emnandi bafana! 🙂
Enkosi ngokuhlala nathi. Ngaba uyawathanda amanqaku ethu? Ngaba ufuna ukubona umxholo onomdla ngakumbi? Sixhase ngokufaka iodolo okanye ngokucebisa abahlobo, I-30% isaphulelo kubasebenzisi beHabr kwi-analogue ekhethekileyo yeeseva zomgangatho wokungena, eyenzelwe wena: (ifumaneka nge-RAID1 kunye ne-RAID10, ukuya kuthi ga kwi-24 cores kunye ne-40GB DDR4).
I-Dell R730xd 2 amaxesha aphantsi? Kuphela apha eNetherlands! Dell R420 - 2x E5-2430 2.2Ghz 6C 128GB DDR3 2x960GB SSD 1Gbps 100TB - ukusuka $99! Funda malunga
umthombo: www.habr.com