SUPPLEMENTARY INFORMATION Letters https://doi.org/.38/s4567-8-5- In the formt provided y the uthors nd unedited. Amplifiction of intense light fields y nerly free electrons Mry Mtthews *, Felipe Morles 2, Alexnder Pts 3, Alrecht Lindinger 3, Julien Gteu, Nicols Berti, Sylvin Hermelin, Jérôme Ksprin, Mri Richter 2,4, Timm Bredtmnn 2, Olg Smirnov 2, Jen-Pierre Wolf nd Mish Ivnov 2 GAP, University of Genev, Genev, Switzerlnd. 2 Mx-Born-Institut für Nichtlinere Optik und Kurzzeitspektroskopie, Berlin, Germny. 3 Inst. für Exp. Physik, Freie Universitt Berlin, Berlin, Germny. 4 Deprtmento de Químic, Módulo 3, Universidd Autónom de Mdrid, Mdrid, Spin. *e-mil: Mry.mtthews@unige.ch Nture Physics www.nture.com/nturephysics 28 Mcmilln Pulishers Limited, prt of Springer Nture. All rights reserved.
Amplifiction of intense light fields y nerly free electrons Supplementry Mteril Mry Mtthews, Felipe Morles2, Alexnder Pts3, Alrecht Lindinger3, Julien Gteu, Nicols Berti, Sylvin Hermelin, Jérôme Ksprin, Mri Richter4, Timm Bredtmnn2, Olg Smirnov2, Jen-Pierre Wolf, Mish Ivnov2 GAP, University of Genev, Genev, Switzerlnd 2 3 4 Mx Born Institute, Berlin, Germny Inst. Fur Exp. Physik, Freie Universitt Berlin, Berlin, Germny Deprtmento de Quimic, Universidd Autonom de Mdrid, Mdrid, Spin Contents: Supplementry Figures 8 Supplementry Text: Note on control of lsing
Supplementry Figure Spectrometer: Side spectrum Spectrometer: Forwrd spectrum A CW-pumped lser oscilltor gives 6 nj/pulse t 8 MHz, with 4 fs. This is mplified using multipss mplifier t khz,.4 mj per pulse nd 4 fs t 87 nm. Sphericl mirror R=4 mm First stge filmenttion Amplifier Chirped mirror pir with ~-6 fs2 / rd / doule ounce over 6 nm- nm Sphericl mirror R=5 mm Sphericl mirror R=25 mm Gs chmer Filment Microphone Off-xis mirror f=3 mm Second stge filmenttion Sphericl mirror R=3 mm Second set of chirped mirror pir with ~-4 fs2 / rd / doule ounce over 6 nm- nm 5 fs 2 nm Concve cylindricl mirrors Digitl cmer : Filment size To Argon cell (Supplementry Figure ) Grting pir 3 l/mm, 6 nm Blze Liquid Crystl Sptil Light Modultor Supplementry Figure. Illustrtions of the lser pulse shping system nd the filmenttion set up within pressured Argon cell. () shows the pressured Argon cell, where shped pulse is focused inside with either sphericl focusing mirror or n off xis prolic mirror, (f=3 cm), nd forwrd nd side spectr mesurement re tken with Ocen Optics HR4 spectrometers. Filment length is monitored with Nikon cmer while the shock wve due to the plsm cretion is monitored with microphone. The mirrors re coted for rodnd reflectivity, nd the gold off-xis prolic mirror hs focl length of 3 cm. We use ultr violet fused silic windows nd lenses, for the cell nd focusing into the spectrometers. Detils of the rodnd lser nd pulse shping nd compression system cn e found in Methods Refs. [36] nd [38]. () shows n illustrtion of lser system used to generte pulse shpes: we use frequency-douled Nd:Vndte lser (Verdi V5, Coherent) to pump Ti:Spphire oscilltor (Femtosource Compct, Femtolsers) to produce 6 nj centered t 85 nm, 9 nm ndwidth t 8 MHz. This seeds multi-pss Ti:Spphire chirped pulse mplifiction (Odin C, Quntronix) t khz, pumped with nnosecond frequency-douled Nd:YLF. The mplified pulses re t 87 nm with ndwidth of 46 nm, energy rnging from.4 to.4 mj nd pulse durtions of su 4 fs. A first stge of filmenttion in ir, using 2.5 m sphericl mirror, gives moderte rodening with pulse energy of 43 μj. Following collimtion nd compression, (two doule ounces on GVD-oscilltion compensted chirped mirror pir (Lyertec)), second stge of filmenttion is performed, with.25m focusing sphericl mirror. Further compression is then completed with chirped mirror pir (Lyertec). Silver flt mirrors
Supplementry Figure 2 Emission spectrl intensity t 627nm (r. units) Dependence on n emission pek, (t 627nm),.8 on the input seeding spectrum. The input seeding spectrum is modified using Gussin spectrl msk..6.4.2. Seeding spectrl intensity t 627nm (r. units) Forwrd emission spectr from filmenttion of pulse shpes with different input spectrl widths Spectrl intensity (r. units).9.8.7 nm.5 3 nm.4.3 6 nm.2 2 nm. Spectrl intensity (r. units) 7 nm 8 nm.6 5 c 5 nm.8 No Gussin msk 55 6 65 7 75 Input spectr showing different widths resulting from Gussin msk 7 nm 8 nm.6 nm 3 nm.4 6 nm.2 4 5 nm 2 nm 45 5 55 6 65 7 75 8 85 9 95 No Gussin msk Supplementry Figure 2 The dependence of the spectrl intensity of resonnt lsing pek on the intensity of the input seeding spectrum. () shows the dependence of lsing pek t 625 nm on the intensity of the seeding spectrum t 624 nm - 626 nm while () shows the oserved forwrd emission spectr. The seeding spectrl intensity is controlled y pplying series of Gussin spectrl msks to the input spectrum, to grdully reduce the supercontinuum til. The Gussin spectrl msks re shown in (c). The rise time, nd the pulse durtion remin short, (su 8 fs), nd the overll pulse energy is kept constnt. There is cler dependence on the seed rdition, indictive of stimulted rther thn mplified spontneous emission.
Supplementry Figure 3 6 Totl emission or sorption t 627nm Emission from non resonnt spectrl region t 655nm Emission from resonnce pek t 627nm Input spectrl power 4 2 Pek emission (r.units) 8 Lsing threshold where sorption ecomes gin 6 4 2 2 Dressed stte popultion not yet creted.5 Dressed stte popultion experiences sorption.5 Input pulse power (GW) 2 2.5 Supplementry Figure 3. The dependence of spectrl intensity of resonnt lsing pek on the input power of the shped pulse. We plot the output spectrl power of the emission pek, (t 625 nm) s well s n djcent region of supercontinuum (t 655 nm) ginst the input dressing pulse power, for the trpezoid pulse, shped s fs 5 fs - fs. For the resonnt pek t 625 nm nd non-resonnt region t 655 nm, the resonnt pek increses with grdient of six times the rte of the non-resonnt spectrl region. Sutrcting the input spectrum, we oserve n sorption region followed y lsing threshold point nd gin region.
Supplementry Figure 4 Reconstruction of phse Temporl reconstruction of ultrshort pulse.8.6.6.4.4.2.2 55 8 6 6 4 65 2 7 75 2 4 8 6 8 85 9 Reconstructed phse from SPIDER Intensity [r. units].8 5 Input spectrum 5.4.2 c 95 Reconstructed spectrum from SPIDER.6 55 phse Intensity [r. units].8 phse 5 6 65 7 75 8 85 9 95 Intensity [r. units].8 SPIDER Interferogrm.6.4.2 34 36 38 4 42 44 46 Supplementry Figure 4. SPIDER mesurements nd pulse reconstruction of n ultrshort pulse. The SPIDER ws tken y plcing piece of Aluminium foil t the centre of the lser filment inside the Argon chmer. A hole ws drilled y the pulse t high intensity, which llowed the pssge of the centrl region of the pulse, removing the photon th round the filment nd reducing the intensity, efore input into the Venteon SPIDER. Tests were performed oth outside nd inside the cell, with known chirp dded using the pulse shper, to confirm the ccurcy of the reconstructions. () shows the pulse temporl reconstruction nd phse, () shows the spectrl reconstruction nd (c) shows the rw interferogrm. The mesurements re t the limit of the ndwidth of the crystl, nd the contriution of short wvelengths is underestimted due to the comprtively lower power of supercontinuum til.
Supplementry Figure 5.9.8.8.8.7.7.6.6.5.5.4.4.3.3.2.2.2... 4 2 2 4 Reconstructed phse Reconstructed pulse shpe Input pulse Signl intensity (r. units).9 Phse.9 6.7.6.5.4.3 4 6.9.8.8.8.7.7.6.6.5.5.4.4.3.3.2.2.2... 2 2 4 6 5.9 4 44 46 48 Input spectrum positive swtooth Input spectrum negtive swtooth.9 6 42 d Signl intensity (r. units) Intensity (r. units) Positive Swtooth Interferogrm Negtive Swtooth interferogrm c Phse Intensity (r.units) Reconstructed pulse shpe Reconstructed phse Input pulse.7.6.5.4.3 6 7 8 9 Supplementry Figure 5. SPIDER mesurements nd pulse reconstruction of symmetric tringulr pulses, with fst rise nd slow decy or vice vers. The SPIDER interferogrms re tken t the position of the filment, y piercing sheet of luminum foil to tke only the centrl region of the pulse in spce nd remove the photon th. The reduced energy of the centrl region ws then fed into Venteon SPIDER nd n interferogrm trce ws recorded. () shows positive swtooth, with fst rise time, with the reconstructed phse nd temporl shpe. The input pulse shpe, (without precompenstion), is overlid in drk lue. () shows the negtive swtooth reconstruction nd input pulse. (c) shows the corresponding interferogrms, nd (d) shows the input spectrum. There is good greement, nd we retrieve equl ut opposite temporl phses. The mesurements re t the limit of the ndwidth of the crystl, nd the contriution of short wvelengths is underestimted due to the comprtively lower power of supercontinuum til.
Spectrl intensity (r.units) Supplementry Figure 6 45 Input white light spectrum efore Sptil Light Modultor 5 55 6 65 7 75 8 85 9 95 Supplementry Figure 6. White light input spectrum without pulse shping, following two stge filmenttion. The spectrum is centred round 78 nm.
Supplementry Figure 7 Spectrl intensity (r. units) Krypton Spectrl intensity (r. units) Argon 58 6 62 64 58 6 62 64 Forwrd emission from ultrshort Gussin pulse, <7 fs Forwrd emission from -- fs trpezoid pulse Forwrd emission spectrum for -4- fs trpezoid pulse shpe Supplementry Figure 7. Direct Comprison etween Argon nd Krypton gses for n ultrshort, 7 fs pulse. () shows Argon nd (), Krypton. The strong emission fetures re locted etween 58nm nd 64nm, ut t different loctions, reflecting the different trnsitions in the lser dressed tom.
Supplementry Figure 8 Pulse shpe clculted from filmenttion propgtion code Experimentl pulse shpe, efore dispersion compenstion z = 29.5 cm I = 76 TW/cm2.8 Intensity (r. units) Intensity (r. units).8.6.4.2-5 c - -5 5.4-5 5 d z = 29.7 cm I = 83 TW/cm2 - -5.6.4.2 5 5 Mximum Intensity during propgtion 8 Intensity (TW.cm-2).8 Intensity (r. units).6.2-5 z = 29.6 cm I = 8 TW/cm2 c 6 4 2 - -5 5 5 28 29 3 3 Distnce (cm) Supplementry Figure 8. Propgtion simultions of lser filmenttion for pulse shpe with fs rise- fs plteu fs decy. (), () nd (c) show the pulse temporl form t three different longitudinl positions t the onset of filmenttion. (see Methods for clcultion detils). Overlid is the desired pulse temporl shpe. (d) shows the intensity chnge cross the filmenttion region of ~5mm. The clculted filmenttion spectrum is shown in Figure 3 () of the text.
Supplementry Text A note on control of lsing. We hve lredy demonstrted the sensitivity of lsing to the seed spectrum. We show tht y ltering the pulse shpe durtion, we chnge the reltive popultions of the dressed sttes. In Argon, trpezoid with fs plteu leds to the emergence of resonnce t 6nm, not present in the 5 fs plteu pulse, (see Figure 2). In Krypton, Figure 4, moving from short, ~5fs pulse to 4 fs trpezoid leds to distinctly different spectrum, with new trnsitions ppering (66nm) nd others no longer visile, (59nm nd 68nm). Thus, the dependence on the seeding spectrum (i.e. the supercontinuum til of the input spectrum) nd on the dressing pulse shpe llows us to enhnce selected lsing wvelengths while suppressing others.