Ultra fast laser yesainzi yeattosecond

Laser inokurumidza zvikuruyesainzi yeattosecond
Parizvino, attosecond pulses inowanikwa zvakanyanya kuburikidza ne high-order harmonic generation (HHG) inotungamirwa neminda yakasimba. Hunhu hwekugadzirwa kwayo hunogona kunzwisiswa semaerekitironi ari ionized, anokurumidza, uye akabatanidzwazve nesimba rakasimba relaser electric field kuti abudise simba, nokudaro achiburitsa attosecond XUV pulses.
Saka, attosecond output inonyanya kuenderana nehupamhi hwepulse, simba, urefu hwewavelength, uye chiyero chekudzokorora kwelaser yekutyaira(Ultra fast laser): pulse width pfupi inobatsira pakuparadzanisa attosecond pulses, simba rakawanda rinovandudza ionization uye kushanda zvakanaka, wavelength yakareba inokwidza cutoff energy asi inoderedza zvakanyanya conversion efficiency, uye high repetition rate inovandudza signal-to-noise ratio asi inogumira kuburikidza ne single pulse energy. Mashandisirwo akasiyana (akadai se electron microscopy, X-ray absorption spectroscopy, coincidence counting, nezvimwewo) ane kusimbiswa kwakasiyana pa attosecond pulse index, iyo inopa zvinodiwa zvakasiyana uye zvakakwana zvekutyaira lasers. Kuvandudza mashandiro ekutyaira lasers kwakakosha kuti ishandiswe mune attosecond science.

Nzira ina huru dzehunyanzvi dzekuvandudza mashandiro emagetsi ekutyaira (Ultra fast laser)
1. Simba repamusoro: Rakagadzirirwa kukunda kushanda kweHHG kushoma uye kuwana ma "high-throughput attosecond pulses". Kushanduka kwetekinoroji kwakachinja kubva ku "traditional chirped pulse amplification" (CPA) kuenda ku "optical parametric amplification family", kusanganisira "optical parametric chirped pulse amplification" (OPCPA), "dual chirped OPA (DC-OPA), "frequency domain OPA (FOPA), uye "quasi phase matching OPCPA (QPCPA). Kubatanidzazve matekiniki e "coherent beam synthesis" (CBC) uye "pulse splitting amplification" (DPA) synthesis kuti kukunde zvipingamupinyi zve "single channel amplifiers", zvakaita se "thermal effects" uye "nonlinear damage", uye kuwana Joule level energy output".
2. Upamhi hwepulse pfupi: Yakagadzirwa kugadzira mapulse e-attosecond akaparadzana anogona kushandiswa kuongorora electronic dynamics, inoda mapulse mashoma kana kunyange e-sub periodic driving uye stable carrier envelope phase (CEP). Matekinoroji makuru anosanganisira kushandisa nzira dzisina kusimba dze post compression dzakadai se hollow core fiber (HCF), multi thin film (MPSC), uye multi-channel cavity (MPC) kudzvanya upamhi hwepulse kusvika pakureba kupfupika. Kugadzikana kweCEP kunoyerwa uchishandisa f-2f interferometer uye kunowanikwa kuburikidza ne active feedback/feedforward (senge AOFS, AOPDF) kana passive all-optical self stabilization mechanisms zvichibva pamaitiro ekusiyana kwema frequency.
3. Kureba kwehurefu hwemafungu: Yakagadzirwa kuti isundire simba re photon rechipiri ku "water window" bhendi remifananidzo ye biomolecule. Nzira nhatu huru dzetekinoroji ndeidzi:
Optical parametric amplification (OPA) uye cascade yayo: Ndiyo mhinduro huru iri pakati pe1-5 μ m wavelength range, ichishandisa makristaro akadai seBiBO neMgO: LN; >Makristaro akadai seZGP neLiGaS ₂ anodiwa kune 5 μ m wavelength band.
Kugadzira MaFrequency Ekuchinjana (DFG) uye Intra Pulse Differential Frequency (IPDFG): zvinogona kupa mbeu kugadzikana kweCEP.
Tekinoroji yelaser yakananga, yakaita seCr: ZnS/Se transition metal doped chalcogenide lasers, inozivikanwa se "mid infrared titanium sapphire" uye ine zvakanakira zvechimiro chakabatana uye kushanda zvakanaka.
4. Kudzokorora kwakanyanya: kwakanangana nekuvandudza chiyero chesignali-ku-ruzha uye kugona kwekuwana data, uye kugadzirisa miganhu yemhedzisiro yekuchaja kwenzvimbo. Nzira mbiri huru:
Tekinoroji yekuwedzera maburi eResonance: kushandisa maburi eresonant akanyatsogadzirwa kuti kuwedzere simba repamusoro remapuru erepetitive frequency pulses emegahertz level kuti kufambise HHG, kwave kuchishandiswa munzvimbo dzakadai semapuru eXUV frequency, asi kugadzira mapuru eattosecond akaparadzana kuchiri kukonzera matambudziko.
Kudzokorora kwakanyanya uyelaser ine simba guruDirect drive, kusanganisira OPCPA, fiber CPA pamwe chete ne nonlinear post compression, uye thin film oscillator, yakawana kugadzirwa kwepulse kweattosecond second pamwero wekudzokorora we100 kHz.