Ngā whanaketanga i roto i te ultraviolet tino nuihangarau pūtake mārama
I ngā tau tata nei, kua aro nui te marea ki ngā pūtake hihi ultraviolet teitei i roto i te mara o ngā hihiri irahiko nā te kaha o te hononga, te poto o te roa o te pao me te kaha o te photon, ā, kua whakamahia i roto i ngā rangahau hihi me te whakaahua. Nā te whanaketanga o te hangarau, kuapūtake māramaKei te whanake haere ki te auau auau teitei ake, te rere o te photon teitei ake, te kaha photon teitei ake, me te whānui o te pāorooro poto ake. Ehara i te mea ka arotau noa tēnei ahunga whakamua i te taumira ine o ngā pūtake mārama ultraviolet tino nui, engari ka whakarato hoki i ngā huarahi hou mō ngā au whanaketanga hangarau ā muri ake nei. Nō reira, he mea nui te ako hohonu me te mārama ki te pūtake mārama ultraviolet tino nui me te auau auau teitei hei whakahaere me te whakamahi i ngā hangarau hou.
Mō ngā inenga mātai irahiko i runga i ngā tauine wā femtosecond me attosecond, he maha ngā wā kāore e ranea te maha o ngā huihuinga i inehia i roto i te hihi kotahi, ā, kāore e ranea ngā pūtake mārama auau iti hei whiwhi tatauranga pono. I taua wā anō, ka whakaitihia e te pūtake mārama he iti te rerenga photon te ōwehenga tohu-ki-haruru o te whakaahua moroiti i te wā whakaaturanga iti. Mā te tūhuratanga me ngā whakamātautau tonu, he maha ngā whakapainga kua mahia e ngā kairangahau i roto i te arotautanga hua me te hoahoa tuku o te mārama ultraviolet tino auau auau teitei. Kua whakamahia te hangarau tātari spectral matatau i honoa ki te pūtake mārama ultraviolet tino auau auau teitei hei whakatutuki i te ine tika o te hanganga rauemi me te tukanga hihiri hiko.
Ko ngā tono o ngā pūtake mārama ultraviolet tino nui, pērā i ngā inenga o te angular resolved electron spectroscopy (ARPES), me whai hihi o te mārama ultraviolet tino nui hei whakamārama i te tauira. Ka whakaohokia ngā irahiko i runga i te mata o te tauira ki te āhua tonu e te mārama ultraviolet tino nui, ā, kei roto i te pūngao nekeneke me te koki tukunga o ngā irahiko whakaahua ngā mōhiohio hanganga roopu o te tauira. Ka whiwhi te tātari irahiko me te mahi koki taumira i ngā irahiko whakaahua kua whakapūatatia, ā, ka whiwhi i te hanganga roopu tata ki te roopu valence o te tauira. Mō te pūtake mārama ultraviolet tino nui, he auau iti te auau tāruarua, nā te mea he nui ngā photon kei roto i tana pā kotahi, ka whakaohokia e ia he maha ngā photon i runga i te mata o te tauira i roto i te wā poto, ā, ka puta he whānui nui o te tohatoha o te pūngao nekeneke o te irahiko whakaahua mā te taunekeneke Coulomb, e kiia nei ko te pānga utu wāhi. Hei whakaiti i te awe o te pānga utu wāhi, me whakaiti ngā irahiko whakaahua kei roto i ia pā me te pupuri tonu i te rere photon pumau, nō reira me akiaki terēserime te auau auau teitei hei whakaputa i te pūtake mārama ultraviolet tino kaha me te auau auau teitei.
Mā te hangarau kōhao whakarei ake i te haruru ka taea te whakaputa i ngā haruru oro teitei i te auau auau MHz.
Hei whiwhi i tētahi pūtake mārama ultraviolet tino kaha me te tere whakahokinga tae atu ki te 60 MHz, i whakahaerehia e te tīma Jones i te Whare Wānanga o British Columbia i te United Kingdom te whakaputanga harmonic ota teitei i roto i te kōhao whakarei ake i te resonance femtosecond (fsEC) hei whakatutuki i tētahi pūtake mārama ultraviolet tino kaha, ā, i whakamahia ki ngā whakamātautau irahiko whakatau koki wā-whakatau (Tr-ARPES). Ka taea e te pūtake mārama te tuku i te rerenga photon neke atu i te 1011 ngā tau photon ia hekona me te harmonic kotahi i te tere whakahokinga o te 60 MHz i roto i te awhe pūngao o te 8 ki te 40 eV. I whakamahia e rātou he pūnaha laser muka kua tāpirihia ki te ytterbium hei pūtake purapura mō te fsEC, ā, i whakahaerehia ngā āhuatanga pāorooro mā te hoahoa pūnaha laser kua whakaritea hei whakaiti i te haruru auau taupatupatu kawe (fCEO) me te pupuri i ngā āhuatanga pēhanga pāorooro pai i te mutunga o te mekameka whakakaha. Hei whakatutuki i te whakarei ake i te auorotanga pumau i roto i te fsEC, e toru ngā koropiko whakahaere servo e whakamahia ana hei whakahaere urupare, ka hua ake he pumau kaha i ngā nekehanga herekore e rua: ko te wā haerenga hoki-mai o te huringa pātere i roto i te fsEC e ōrite ana ki te wā pātere taiaho, me te nekehanga ā-wāhanga o te kaikawe mara hiko e pā ana ki te kōpaki pātere (arā, te wāhanga kōpaki kaikawe, ϕCEO).
Mā te whakamahi i te hau krypton hei hau mahi, i tutuki i te tīma rangahau te whakaputanga o ngā harmonika teitei ake i roto i te fsEC. I whakahaerehia e rātou ngā inenga Tr-ARPES o te karāpeti, ā, i kitea te whakamahana tere me te whakakotahitanga puhoi o ngā taupori irahiko kāore i te whakaohohia e te wera, me te hihiri o ngā āhua whakaoho tika kāore i te wera tata ki te taumata Fermi i runga ake i te 0.6 eV. He taputapu nui tēnei pūtake mārama mō te ako i te hanganga hiko o ngā rauemi uaua. Heoi, he tino teitei ngā whakaritenga mō te whakaata, te utu marara, te whakatikatika pai o te roa o te kōhao me te raka tukutahitanga o te whakaputanga o ngā harmonika teitei ake i roto i te fsEC, ka pā nui ki te maha whakarei ake o te kōhao whakarei ake i te oro. I taua wā anō, he wero anō hoki te urupare ā-wāhanga kore-raina o te plasma i te pūwāhi arotahi o te kōhao. Nō reira, i tēnei wā, kāore anō tēnei momo pūtake mārama kia waiho hei ultraviolet tino nui.pūtake māramatanga harmonic teitei.
Wā tuku: 29 Paenga-whāwhā 2024