Cited by 91Quantum, superfluid, helium dynamicsAdvanced X-ray Imaging TechniquesLaser-Matter Interactions and Applications

The DOI matches its Crossref record; 52 of the 52 references it cites were found in a registry or an index.

Coherent diffractive imaging of single helium nanodroplets with a high harmonic generation source

Open access

Abstract

Coherent diffractive imaging of individual free nanoparticles has opened routes for the in situ analysis of their transient structural, optical, and electronic properties. So far, single-shot single-particle diffraction was assumed to be feasible only at extreme ultraviolet and X-ray free-electron lasers, restricting this research field to large-scale facilities. Here we demonstrate single-shot imaging of isolated helium nanodroplets using extreme ultraviolet pulses from a femtosecond-laser-driven high harmonic source. We obtain bright wide-angle scattering patterns, that allow us to uniquely identify hitherto unresolved prolate shapes of superfluid helium droplets. Our results mark the advent of single-shot gas-phase nanoscopy with lab-based short-wavelength pulses and pave the way to ultrafast coherent diffractive imaging with phase-controlled multicolor fields and attosecond pulses.

Overview

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1038/s41467-017-00287-z

Cites

52 of 52 references verified0 citation errors · 0 not checkable

Statistics

Figures

Fig. 1 Scheme of the experimental setup. A Ti:sapphire laser with 792 nm central wavelength and 35 fs pulse duration is used for the generation of high harmonics. Up to 12 mJ are loosely focused into a xenon-filled cell, where the extreme ultraviolet (XUV) pulses are produced. The copropagating near-infrared (NIR) beam is removed via a Mo/Si mirror and a thin aluminum filter. The beam is focused to a small spot (ω0 = 10 μm) using a coma-correcting system of three gold-coated toroidal mirrors26. A pulsed jet of helium nanodroplets (R¯ ≈ 400 nm) is overlapped with the XUV focus. The overlap is optimized by monitoring the formation of He+ ions using an ion time-of-flight spectrometer. The scattering signal is amplified by a pulsed MCP and converted to optical photons on a phosphor screen. The single-shot diffraction images are captured with an out-of-vacuum camera (not depicted)
Fig. 1 Scheme of the experimental setup. A Ti:sapphire laser with 792 nm central wavelength and 35 fs pulse duration is used for the generation of high harmonics. Up to 12 mJ are loosely focused into a xenon-filled cell, where the extreme ultraviolet (XUV) pulses are produced. The copropagating near-infrared (NIR) beam is removed via a Mo/Si mirror and a thin aluminum filter. The beam is focused to a small spot (ω0 = 10 μm) using a coma-correcting system of three gold-coated toroidal mirrors26. A pulsed jet of helium nanodroplets (R¯ ≈ 400 nm) is overlapped with the XUV focus. The overlap is optimized by monitoring the formation of He+ ions using an ion time-of-flight spectrometer. The scattering signal is amplified by a pulsed MCP and converted to optical photons on a phosphor screen. The single-shot diffraction images are captured with an out-of-vacuum camera (not depicted)CC BY · PubMed Central
Fig. 2 Multicolor analysis of the diffraction images. a Measured bright scattering image (center part of the detector, intensity in arbitrary units) from a spherical droplet with a pronounced concentric ring pattern. b, c Multicolor Mie fits (dashed purple) of the extracted radial intensity profile (solid black) from a as obtained via a simplex optimization (see “Methods” section) of the individual harmonic contributions to the profiles (color-coded in green, blue, red, and yellow). The results illustrate that two qualitatively different solutions yield comparably small residuals. The two solutions indicate that either the 13th harmonic b or the 15th harmonic c dominates. The resulting refractive indices of these and all other fits are given in Supplementary Fig. 4. d Measured average extreme ultraviolet spectrum of the high harmonic radiation. e Sketch of the energy-dependent refractive indices of bulk liquid helium in the vicinity of the helium 1s–2p transition, assembled from bulk liquid helium measurements31, 32 (solid lines, color-coded in light-gray and dark-gray) and tabulated values (scatter, NIST database, http://physics.nist.gov/PhysRefData/FFast/html/form.html)
Fig. 2 Multicolor analysis of the diffraction images. a Measured bright scattering image (center part of the detector, intensity in arbitrary units) from a spherical droplet with a pronounced concentric ring pattern. b, c Multicolor Mie fits (dashed purple) of the extracted radial intensity profile (solid black) from a as obtained via a simplex optimization (see “Methods” section) of the individual harmonic contributions to the profiles (color-coded in green, blue, red, and yellow). The results illustrate that two qualitatively different solutions yield comparably small residuals. The two solutions indicate that either the 13th harmonic b or the 15th harmonic c dominates. The resulting refractive indices of these and all other fits are given in Supplementary Fig. 4. d Measured average extreme ultraviolet spectrum of the high harmonic radiation. e Sketch of the energy-dependent refractive indices of bulk liquid helium in the vicinity of the helium 1s–2p transition, assembled from bulk liquid helium measurements31, 32 (solid lines, color-coded in light-gray and dark-gray) and tabulated values (scatter, NIST database, http://physics.nist.gov/PhysRefData/FFast/html/form.html)CC BY · PubMed Central
Fig. 3 Three characteristic types of diffraction images from helium nanodroplets. The majority of images contains concentric ring patterns a, b that are assigned to spherical droplets. Elliptical ring structures as in c or pronounced streak patterns as in d-f reflect deformed helium droplets. The measured dataset comprises 1762 ring-type, 421 elliptical, and 68 streak-type images. In most cases, the latter exhibit a clear bending of the streaks (55 out of 68 images), e.g., as in d and f. For details, see Supplementary Note 3. False color images, color bar applies to all patterns, intensity in arbitrary units
Fig. 3 Three characteristic types of diffraction images from helium nanodroplets. The majority of images contains concentric ring patterns a, b that are assigned to spherical droplets. Elliptical ring structures as in c or pronounced streak patterns as in d-f reflect deformed helium droplets. The measured dataset comprises 1762 ring-type, 421 elliptical, and 68 streak-type images. In most cases, the latter exhibit a clear bending of the streaks (55 out of 68 images), e.g., as in d and f. For details, see Supplementary Note 3. False color images, color bar applies to all patterns, intensity in arbitrary unitsCC BY · PubMed Central
Fig. 4 Unique identification of prolate pill-shaped structures. a Measured image (intensity in arbitrary units) and b matching simulation result of the wide-angle diffraction of a pill-shaped prolate droplet (logarithmic intensity in arbitrary units, color bar applies also to d–f). The structure shape and orientation are visualized in yellow. The optical axis of the extreme ultraviolet beam is directed into the image plane, the tilt angle between the symmetry axis of the particle and the optical axis is 35°; the semi-minor axes a = b = 370 nm and the semi-major axis c = 950 nm; for optical parameters see “Methods” section. c Illustration of the origin of bent streaks occurring when a tilted rod-type structure diffracts the light. The constructive interference is analogous to the specular reflection at the surface of a macroscopic rod. Two particular bundles of constructively interfering rays are explicitly sketched, please note that the different ray colors do not refer to wavelengths, but are applied to facilitate distinction. d Simulated wide-angle diffraction image of a wheel-shaped oblate particle (semi-major/-minor axes as in b, tilt angle of 80° between the symmetry axis and the optical axis, which is directed into the image plane). If the oblate particle’s symmetry axis is neither oriented along the optical axis nor perpendicular to it, the diffraction patterns exhibit straight streaks to only one side. e, f Comparison of simulated wide-angle diffraction images of a prolate e and an oblate structure f aligned to the scattering plane, i.e., at 90° tilt angle between the symmetry axis and the optical axis, other parameters as in b, d. Though the 2D projections are similar and the 2D outlines identical, the intensity distributions of the straight streaks are clearly different and decay much faster for wheel-type than for pill-type shapes
Fig. 4 Unique identification of prolate pill-shaped structures. a Measured image (intensity in arbitrary units) and b matching simulation result of the wide-angle diffraction of a pill-shaped prolate droplet (logarithmic intensity in arbitrary units, color bar applies also to d–f). The structure shape and orientation are visualized in yellow. The optical axis of the extreme ultraviolet beam is directed into the image plane, the tilt angle between the symmetry axis of the particle and the optical axis is 35°; the semi-minor axes a = b = 370 nm and the semi-major axis c = 950 nm; for optical parameters see “Methods” section. c Illustration of the origin of bent streaks occurring when a tilted rod-type structure diffracts the light. The constructive interference is analogous to the specular reflection at the surface of a macroscopic rod. Two particular bundles of constructively interfering rays are explicitly sketched, please note that the different ray colors do not refer to wavelengths, but are applied to facilitate distinction. d Simulated wide-angle diffraction image of a wheel-shaped oblate particle (semi-major/-minor axes as in b, tilt angle of 80° between the symmetry axis and the optical axis, which is directed into the image plane). If the oblate particle’s symmetry axis is neither oriented along the optical axis nor perpendicular to it, the diffraction patterns exhibit straight streaks to only one side. e, f Comparison of simulated wide-angle diffraction images of a prolate e and an oblate structure f aligned to the scattering plane, i.e., at 90° tilt angle between the symmetry axis and the optical axis, other parameters as in b, d. Though the 2D projections are similar and the 2D outlines identical, the intensity distributions of the straight streaks are clearly different and decay much faster for wheel-type than for pill-type shapesCC BY · PubMed Central

Verification

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Citations

Cites

Show all 52 references

Research works printed but not linked: 1

  1. Gomez, L. et al. Supplemental material to: Shapes and vorticities of superfluid helium nanodroplets. Science 345, 906–909 (2014). · DOI · Paper page

Cited by

Sorted by citations

See all 91

Metadata

Authors
Rupp, D., Monserud, N., Langbehn, B., Sauppe, M., Zimmermann, J., Ovcharenko, Y., Möller, T., Frassetto, F., Poletto, L., Trabattoni, A., Calegari, F., Nisoli, M., Sander, K., Peltz, C., J. Vrakking, M., Fennel, T., & Rouzée, A.
Affiliations
  • Technische Universität Berlin (DE)
  • Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy (DE)
  • Istituto di Fotonica e Nanotecnologie (IT)
  • Deutsches Elektronen-Synchrotron DESY (DE)
  • University of Rostock (DE)
Corresponding author
  • Rupp, Daniela
  • Fennel, Thomas
  • Rouzée, Arnaud
Venue
Nature Communications
Published
2017-09-08
Volume
8
Issue
1
Pages
493-493
ISSN
2041-1723 (ISSN-L)
OpenAlex
W2951302515
Cited by
89
References
52
Citations by year
2026: 3 · 2025: 7 · 2024: 7 · 2023: 6 · 2022: 12 · 2021: 11 · 2020: 19 · 2019: 12 · 2018: 12
FWCI
5.77
Type
journal article
Language
en
Open access
Locations
  • Nature Communications (publishedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • arXiv (Cornell University) (submittedVersion)
  • Virtual Community of Pathological Anatomy (University of Castilla La Mancha) (submittedVersion, cc-by)
  • RePEc: Research Papers in Economics (submittedVersion)
  • Desy Publications Database (Deutsches Elektronen-Synchrotron DESY) (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Refubium (Universitätsbibliothek der Freien Universität Berlin) (submittedVersion, cc-by)
  • Repository for Publications and Research Data (ETH Zurich) (submittedVersion, cc-by)
  • arXiv (Cornell University)
  • Universitätsbibliothek der FU Berlin Hochschulschriftenstelle u. Dokumentenserver (cc-by)
  • ETH Zürich Research Collection (cc-by)
Funders
  • European Commission (637756, 641789, HORIZON2020)
  • Deutsche Forschungsgemeinschaft (SFB652/3, MO 719/13, SFB 652, MO 719/13-1, 719/13, FE 1120/4-1)
  • Bundesministerium für Bildung und Forschung (05K16HRB, 05K13KT2)
  • FP7 Ideas: European Research Council (227355)
Topics
  • Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum, superfluid, helium dynamics
  • Physical Sciences › Physics and Astronomy › Radiation › Advanced X-ray Imaging Techniques
  • Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Laser-Matter Interactions and Applications
Keywords
coherent diffraction imaging, helium nanodroplets, single-shot imaging, high harmonic generation, extreme ultraviolet pulses, femtosecond laser, superfluid helium, prolate shape, single-particle diffraction

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review