Laser mai sauri sosai don kimiyyar attosecond

Laser mai sauri sosaidon kimiyyar attosecond
A halin yanzu, attosecond pulses galibi ana samun su ne ta hanyar samar da harmonic mai girma (HHG) wanda filayen ƙarfi ke jagoranta. Ana iya fahimtar ainihin samar da su a matsayin electrons da ake haɗa su da ion, ana hanzarta su, kuma ana sake haɗa su ta hanyar ƙarfin filin lantarki na laser don fitar da makamashi, ta haka ne ake fitar da attosecond XUV pulses.
Saboda haka, fitowar attosecond tana da matuƙar tasiri ga faɗin bugun jini, kuzari, tsawon rai, da kuma yawan maimaitawa naLaser mai tuƙi(Laser mai sauri): gajeriyar faɗin bugun jini yana da amfani wajen ware bugun attosecond, ƙarin kuzari yana inganta ionization da inganci, tsawon tsayin tsayi yana ɗaga kuzarin yankewa amma yana rage ingancin juyawa sosai, kuma mafi girman saurin maimaitawa yana inganta rabon sigina zuwa hayaniya amma yana iyakance ta hanyar kuzarin bugun jini ɗaya. Aikace-aikace daban-daban (kamar na'urar microscopy ta lantarki, na'urar X-ray absorption spectroscopy, ƙidaya daidaituwa, da sauransu) suna da fifiko daban-daban akan ma'aunin bugun jini na attosecond, wanda ke gabatar da buƙatu daban-daban da cikakkun bayanai don na'urorin laser na tuki. Inganta aikin na'urorin laser na tuki yana da mahimmanci don amfani a kimiyyar attosecond.

Hanyoyi huɗu na fasaha don haɓaka aikin lasers na tuki (Laser mai sauri sosai)
1. Ƙarfin kuzari mafi girma: An ƙera shi don shawo kan ƙarancin ingancin juyawa na HHG da kuma samun bugun attosecond mai ƙarfi. Juyin halittar fasaha ya canza daga ƙara ƙarfin bugun bugun gargajiya (CPA) zuwa dangin ƙara ƙarfin gani, gami da ƙara ƙarfin bugun bugun gani na gani (OPCPA), ƙara ƙarfin bugun zuciya mai ji biyu (DC-OPA), OPA mai mita (FOPA), da kuma daidaitawar OPCPA (QPCPA). Ƙara haɗa dabarun haɗakar hasken haske mai haɗin gwiwa (CBC) da haɓaka ƙarfin bugun zuciya (DPA) don shawo kan iyakokin zahiri na amplifiers na tashoshi ɗaya, kamar tasirin zafi da lalacewar da ba ta layi ba, da kuma cimma fitowar makamashin matakin Joule.
2. Faɗin bugun da ya fi guntu: An ƙera shi don samar da bugun attosecond da aka ware wanda za a iya amfani da shi don nazarin yanayin lantarki, wanda ke buƙatar ƴan ko ma ƙananan bugun tuƙi na lokaci-lokaci da kuma matakin envelope mai karko (CEP). Manyan fasahohin sun haɗa da amfani da dabarun matsa lamba mara layi kamar zare mai zurfi (HCF), fim mai sirara da yawa (MPSC), da rami mai tashoshi da yawa (MPC) don matse faɗin bugun zuwa gajarta sosai. Ana auna kwanciyar hankali na CEP ta amfani da na'urar aunawa ta f-2f kuma ana samun ta ta hanyar amsawa/feedforward mai aiki (kamar AOFS, AOPDF) ko hanyoyin daidaita kai na gani-da-gani waɗanda suka dogara da hanyoyin bambancin mita.
3. Tsawon tsawon zango: An ƙera shi don tura kuzarin photon na attosecond zuwa ga madaurin "tagar ruwa" don ɗaukar hoton biomolecule. Manyan hanyoyin fasaha guda uku sune:
Ƙara girman siginar gani (OPA) da kuma tsarinsa: Ita ce babbar mafita a cikin kewayon tsawon tsayin 1-5 μm, ta amfani da lu'ulu'u kamar BiBO da MgO: LN; >Ana buƙatar lu'ulu'u kamar ZGP da LiGaS ₂ don rukunin tsawon tsayin 5 μm.
Samar da Mita Mai Bambanci (DFG) da Mita Mai Bambancin Kwakwalwa (IPDFG): na iya samar da tushen iri tare da kwanciyar hankali na CEP mara aiki.
Fasahar laser kai tsaye, kamar Cr: ZnS/Se transition metal doped chalcogenide lasers, an san ta da "mid infrared titanium sapphire" kuma tana da fa'idodin tsarin da ya dace da kuma ingantaccen aiki.
4. Mafi girman yawan maimaitawa: da nufin inganta rabon sigina zuwa hayaniya da ingancin tattara bayanai, da kuma magance iyakokin tasirin cajin sarari. Manyan hanyoyi guda biyu:
Fasahar haɓaka ramin resonance: An yi amfani da ramukan resonant masu inganci don haɓaka ƙarfin kololuwar bugun mita mai maimaitawa na matakin megahertz don tuƙi HHG, amma samar da bugun attosecond da aka ware har yanzu yana haifar da ƙalubale.
Babban adadin maimaitawa da kumababban laser mai ƙarfiTuki kai tsaye, gami da OPCPA, fiber CPA tare da matsi mara layi, da kuma siraran oscillator na fim, sun sami nasarar samar da bugun zuciya na attosecond a cikin mita mai maimaitawa na 100 kHz.