Ikilasi le-TW attosecond X-ray pulse laser

Ikilasi le-TW attosecond X-ray pulse laser
I-X-ray yesibilii-pulse laserngamandla aphezulu kanye nobude be-pulse emfushane kuyisihluthulelo sokufinyelela i-spectroscopy ye-ultrafast nonlinear kanye ne-X-ray diffraction imaging. Ithimba labacwaningi e-United States lasebenzisa i-cascade yezigaba ezimbiliI-X-ray yamahhala ye-electron lasersukukhipha ama-discrete attosecond pulses. Uma kuqhathaniswa nemibiko ekhona, amandla aphakeme aphezulu ama-pulses akhuphuka ngohlelo lobukhulu, amandla aphezulu aphezulu yi-1.1 TW, futhi amandla aphakathi angaphezulu kuka-100 μJ. Ucwaningo luphinde lunikeze ubufakazi obuqinile bokuziphatha kwe-soliton-like superradiation emkhakheni we-X-ray.Ama-laser anamandla aphezulubaye bashayela izindawo eziningi ezintsha zocwaningo, okuhlanganisa i-high-field physics, i-attosecond spectroscopy, nama-accelerator ezinhlayiyana ze-laser. Kuzo zonke izinhlobo zama-lasers, ama-X-ray asetshenziswa kakhulu ekuxilongweni kwezokwelapha, ekutholeni amaphutha ezimbonini, ekuhloleni ukuphepha kanye nocwaningo lwesayensi. I-X-ray free-electron laser (XFEL) ingakhuphula amandla e-X-ray aphakeme ngama-oda amaningana wobukhulu uma kuqhathaniswa nobunye ubuchwepheshe bokukhiqiza i-X-ray, ngaleyo ndlela inwebe ukusetshenziswa kwama-X-ray emkhakheni we-spectroscopy engaqondile kanye ne-single- i-particle diffraction imaging lapho kudingeka khona amandla aphezulu. I-attosecond XFEL yakamuva ephumelele impumelelo enkulu kusayensi nobuchwepheshe be-attosecond, ikhulisa amandla aphezulu atholakalayo ngama-oda angaphezu kwesithupha obukhulu uma kuqhathaniswa nemithombo ye-X-ray yebhentshi.

Amalaser e-electron amahhalaingathola amandla okushaya kwenhliziyo ama-oda amaningi obukhulu obuphezulu kunezinga lokuphuma okuzenzakalelayo lisebenzisa ukungazinzi okuhlangene, okubangelwa ukusebenzisana okuqhubekayo kwenkambu yemisebe ku-relativistic electron beam kanye ne-oscillator kazibuthe. Ebangeni le-X-ray eliqinile (cishe u-0.01 nm kuya ku-0.1 nm wavelength), i-FEL ifinyelelwa ngokuminyanisa kwenqwaba kanye namasu okuhlanganisa ama-post-saturation. Ebangeni le-X-ray elithambile (cishe u-0.1 nm kuya ku-10 nm wavelength), i-FEL isetshenziswa ubuchwepheshe be-cascade fresh-slice. Muva nje, ama-attosecond pulses anamandla aphezulu angu-100 GW kubikwe ukuthi akhiqizwa kusetshenziswa indlela ethuthukisiwe yokukhishwa kwe-self-amplified spontaneous emission (ESASE).

Ithimba labacwaningi lisebenzise isistimu yokukhulisa izigaba ezimbili esekelwe ku-XFEL ukuze ikhulise ukuphuma kwe-X-ray attosecond pulse ethambile kusukela ku-linac coherent.umthombo wokukhanyaezingeni le-TW, ukuhleleka kokuthuthukiswa kobukhulu kunemiphumela ebikiwe. Ukusethwa kokuhlola kuboniswa kuMfanekiso 1. Ngokusekelwe endleleni ye-ESASE, i-photocathode emitter iyashintshwa ukuze ithole i-electron beam ene-spike yamanje ephezulu, futhi isetshenziselwa ukukhiqiza ama-atosecond X-ray pulses. I-pulse yokuqala itholakala emaphethelweni angaphambili e-spike ye-electron beam, njengoba kuboniswe ekhoneni eliphezulu kwesokunxele soMfanekiso 1. Lapho i-XFEL ifinyelela ekugcwaliseni, i-electron beam ibambezeleka ngokuhlobene ne-X-ray nge-compressor kazibuthe, bese ukushaya kwenhliziyo kusebenzisana ne-electron beam (ucezu olusha) olungashintshwanga yi-ESASE modulation noma i-FEL laser. Okokugcina, i-undulator kazibuthe yesibili isetshenziselwa ukuqhubeka nokukhulisa ama-X-ray ngokusebenzisana kwe-attosecond pulses nocezu olusha.

I-FIG. 1 Umdwebo wedivayisi yokuhlola; Umfanekiso ubonisa indawo yesigaba se-longitudinal (umdwebo wamandla wesikhathi we-electron, oluhlaza), iphrofayili yamanje (eluhlaza okwesibhakabhaka), kanye nemisebe ekhiqizwa ukukhulisa i-oda lokuqala (okunsomi). I-XTCAV, i-X-band transverse cavity; I-cVMI, uhlelo lokuthwebula imephu olusheshayo lwe-coaxial; FZP, Fresnel band plate plate spectrometer

Wonke ama-attosecond pulses akhiwe ngomsindo, ngakho-ke i-pulse ngayinye inezindawo ezihlukile ze-spectral kanye nesizinda sesikhathi, abacwaningi abazihlola kabanzi. Ngokuphathelene ne-spectra, basebenzise i-spectrometer ye-Fresnel band plate ukuze balinganise i-spectra yama-pulses ngamanye ngobude obuhlukile obulinganayo be-undulator, futhi bathola ukuthi lezi zibukeli zigcina amagagasi abushelelezi ngisho nangemva kokukhuliswa kwesibili, okubonisa ukuthi ama-pulses ahlala engashintshi. Esizindeni sesikhathi, i-angular fringe iyalinganiswa futhi i-waveform yesizinda sesikhathi se-pulse ibonakala. Njengoba kuboniswe kuMfanekiso 1, i-X-ray pulse igqigqene ne-circularly polarized infrared laser pulse. Ama-photoelectrons enziwe i-ioned by the X-ray pulse azokhiqiza ama-streaks abheke ohlangothini oluphambene namandla e-vector we-infrared laser. Ngenxa yokuthi inkambu kagesi ye-laser ijikeleza ngokuhamba kwesikhathi, ukusatshalaliswa komfutho kwe-photoelectron kunqunywa isikhathi sokukhishwa kwe-electron, futhi ubudlelwano phakathi kwemodi ye-angular yesikhathi sokukhishwa kanye nokusatshalaliswa komfutho kwe-photoelectron kuyasungulwa. Ukusatshalaliswa komfutho we-photoelectron kukalwa kusetshenziswa i-spectrometer ye-coaxial yokubona imephu esheshayo. Ngokusekelwe emiphumeleni yokusabalalisa kanye ne-spectral, i-waveform yesizinda sesikhathi se-attosecond pulses ingakhiwa kabusha. Umfanekiso 2 (a) ubonisa ukusatshalaliswa kobude be-pulse, ne-median engu-440 njenge. Ekugcineni, umtshina wokuqapha igesi wasetshenziselwa ukukala amandla okushaya kwenhliziyo, futhi isiqephu sokusabalalisa phakathi kwamandla aphezulu kanye nobude be-pulse njengoba kuboniswe kuMfanekiso 2 (b) kubalwa. Ukucushwa okuthathu kuhambisana nezimo zokugxila ezihlukene ze-electron, izimo ze-waver coning kanye nezimo zokulibaziseka kwe-magnetic compressor. Ukulungiselelwa okuthathu kuveze amandla okushaya kwenhliziyo okumaphakathi okungu-150, 200, kanye no-260 µJ, ngokulandelana, ngamandla aphakeme aphezulu angu-1.1 TW.

Umfanekiso 2. (a) I-histogram yokusabalalisa yobude obuyingxenye yobude obugcwele (FWHM) ubude besilinganiso sokushaya kwenhliziyo; (b) Isakhiwo se-scatter esihambisana namandla aphezulu kanye nobude be-pulse

Ngaphezu kwalokho, ucwaningo luphinde lwabona ngokokuqala ngqa isenzakalo se-soliton-like superemission ebhendini ye-X-ray, ebonakala njengokufinyeza kwenhliziyo okuqhubekayo ngesikhathi sokukhulisa. Kubangelwa ukuxhumana okuqinile phakathi kwama-electron kanye nemisebe, ngamandla adluliswa ngokushesha esuka ku-electron aye ekhanda le-X-ray pulse futhi abuyele ku-electron esuka emsileni we-pulse. Ngokucwaninga okujulile kwalesi senzakalo, kulindeleke ukuthi ama-X-ray pulses anesikhathi esifushane namandla aphakeme aphezulu angase abonakale ngokuqhubekayo ngokwandisa inqubo yokukhulisa i-superradiation nokusebenzisa ithuba lokufinyeza kokushaya kwenhliziyo ngemodi efana ne-soliton.