27 thoughts on “Picture of a Single Atom Wins Science Photo Contest

  1. nycola February 13, 2018 / 2:16 am

    For the curious: a single positively-charged strontium atom

  2. Staggery_Johnson February 13, 2018 / 2:16 am

    I’ve had taken pictures with trillions of atoms in them and I haven’t won a prize or anything.

  3. din7 February 13, 2018 / 2:16 am

    It seems plausible that this was an accident and it’s the first ever atomic photobomb.

  4. apimil February 13, 2018 / 2:16 am

    Soon science will provide me with a mean to take dickpics just like everyone else <3

  5. Mr-frost February 13, 2018 / 2:16 am

    It’s quite big if there’s only 2 mm between the two rods, I thought atoms were alot smaller

  6. spentland February 13, 2018 / 2:16 am

    I can’t believe I’m pinch-to-zoom-ing in to see an atom. WATTBA.

  7. blackenship February 13, 2018 / 2:16 am

    Whole lot of idk what that is going on here in this pic

  8. lewisnwkc February 13, 2018 / 2:16 am

    So what scale are we observing here?

  9. xhris666 February 13, 2018 / 2:16 am

    Hmmm…there’s too many pixels in the picture to be only one atom..

  10. MyDadisAMailMan February 13, 2018 / 2:16 am

    There’s a lot of people asking for more info, so I thought I’d chime in. I’m a graduate student working in a trap-physics related field, so I understand a bit of what’s going on. This photo utilizes Laser Cooling and Ion Trapping, the creators of which were given Nobel Prizes (Laser Cooling in ’97 and trapping in 89) and there’s some cool shit going on.

    This is a photo of a single strontium ion (Sr^+). Because the particle is charged, it is (reasonably) easy to confine the particle to a small area using electric fields. Along the axis (where you see the blue / copper looking pieces), confinement is provided by applying a DC (constant) positive voltage. However, it is impossible to confine a particle in 3-D using purely static (fields that don’t change with time) fields, so a “rotating saddle” potential is formed along the direction(s) perpendicular to the axis. This is typically provided by applying a large potential (~100 Volts? I forget the typical RF voltages, but somewhere along that order of magnitude) oscillating at RF frequencies (~Mega-hertz, ~10^9 Hz). This is hard to picture, so here’s a decent analogy. Imagine instead of a ball, you have a positively charged ion and the RF voltages create the rotating saddle: https://www.youtube.com/watch?v=XTJznUkAmIY

    This type of ion trap is called a Linear Paul Trap.
    See Fig 1a from the following: https://www.researchgate.net/figure/Ions-confined-in-a-trapa-A-linear-quadrupole-ion-trap-known-as-a-Paul-trap-beige_fig4_5291816

    Now, how the **** do you image a single ion? Keep in mind, these particles (there can be hundreds or thousands in a trap!) are oscillating in the trap at various frequencies. If you want to do experiments with them in a very controlled manner, you need to cool (i.e. remove kinetic energy) it. In this case, Sr^+ was chosen because it is capable of being laser cooled. To laser cool, you shoot a laser in at just the right frequency so when the atom is moving toward the laser, it sees the the energy of the laser blue-shifted (it’s energy shifted just below the actual energy required to absorb!) to the correct frequency. The atom then emits a photon and continues it’s oscillation. However, because of the laser de-tuning away from the required energy, the ion effectively emits away a very tiny amount of it’s motional energy. This process is very rapid ( <1s) and can get down to ~0.001 Kelvin. See https://en.wikipedia.org/wiki/Laser_cooling

    Now, how do they image an individual ion? Usually the transitions for laser cooling are in the visible (or near-visible), and so many photons can be absorbed and re-emitted. Typically you see ions imaged with a CCD camera (see Fig 1 of the above link). In this case, with a long exposure you can actually image the (lone) ion in the center of the trap. If you want more evidence, there are tons of papers that have imaged individual ions. Here’s a nice photo where the group has controlled the string of ions by playing with the potentials:


    And here’s a group that made a Coulomb Crystal of thousands of ions, all laser-cooled to milli-Kelvin temps:

    Lastly, to store ions for this long typically requires ultra-high vacuum (verrrrrrrrrrrrrry low pressure). For reference, room temp. air is typically ~1 atm. Ultra-high vacuum is typically around 10^-10 torr, which is roughly ~10^-13 atm, or 0.0000000000001 atmospheres. This is to reduce the chance of the Strontium being knocked out of the trap or neutralizing itself (and then it won’t be trapped anymore) by stealing an electron from a room temperature particle of residual gas.

    EDIT: I forgot to mention: why does the particle appear so big? Those electrodes are probably on the order of ~millimeters, but the real limit here is from the camera used to image the ion. Usually, very precise CCD cameras are used for this type of thing, and even then the particle appears to be ~micrometers across. There are a LOT of photons coming off that thing, and there is still some residual motion, so the ion is emitting light at most points in it’s oscillatory motion around the trap.

    TLDR: Laser cooling, long exposure photo and ion trap in a super good vacuum

  11. SmoovOpRatoR February 13, 2018 / 2:16 am

    How big is this? Where the scale banana.

  12. pperca February 13, 2018 / 2:16 am

    it looks like a spec of dust.

  13. thenewyorkgod February 13, 2018 / 2:16 am

    Its the light gathered from a single atom. The white dot we are looking at is probably 100 billion times the size of an actual atom.

  14. dsfkjsd February 13, 2018 / 2:16 am

    Worst atom I have ever seen.

  15. dude511 February 13, 2018 / 2:16 am

    That atom is the size of my will to live

  16. wi_2 February 13, 2018 / 2:16 am

    This is a photograph of a strontium ion, related to quantum computing

  17. flitbee February 13, 2018 / 2:16 am

    Heisenberg will not be pleased

  18. ramewe February 13, 2018 / 2:16 am

    The photo was captured on August 7th, 2017, using a Canon 5D Mark II DSLR, a Canon EF 50mm f/1.8 lens, extension tubes, and two flash units with color gels.

  19. fourmaples February 13, 2018 / 2:16 am

    I thought atoms were too small to reflect wavelengths of visible light?

  20. JasonAnarchy February 13, 2018 / 2:16 am

    That is an absolutely amazing picture.

  21. Ferl74 February 13, 2018 / 2:16 am

    No I said a picture with my single cousin, Adam.

  22. Saristaa404 February 13, 2018 / 2:16 am

    ELI5: Why does it appear do much larger than it actually is?

  23. ERockEfreedom February 13, 2018 / 2:16 am

    I read this as “single mom” at first. Was thoroughly confused about what science has become.

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