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Optical tweezers for manipulating atoms together to form new structure

  1. Jul 7, 2014 #1
    I am trying to figure out a method for using optical tweezers to manipulate individual atoms into new meta-material structures. I understand this would require a very complicated process. I thought of some general steps this process might use.

    This is roughly what I think it might require.

    1. Detect atoms of interest and their current frequency range.

    2. Adjust frequencies of lasers to match the frequency of the desired atoms.

    3. Apply lasers to the desired atom to cool atom to a manageable temperature. Recalibrate laser frequency as atom is cooled to detected frequency of atom in continuous loop executed automatically through a mechanism that detects atoms position and frequency real time and adjusts lasers frequency and orientations as required.

    4. Once targeted atom is sufficiently cooled to a temperature where tweezing it to new controlled positions is possible, orient lasers to move atom to desired position. It is possible temperature of atom may rise as lasers are continuously being applied to move it. While moving atom real time detection of position and temperature of atom is also required to be used to move atom while keeping its temperature controlled.

    5. Move atom with lasers into positions with other atoms to bond in a way to form desired material structure. Have to find a way to compensate for inter-atomic forces when doing this such as Van der Waals force.

    Does anyone have any suggestions for anything else that would need to be considered in order to do something like this or how this can be done?
  2. jcsd
  3. Jul 7, 2014 #2


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    Start by looking at "optical molasses"; this will get your atoms into the state required.

    http://www.colorado.edu/physics/2000/bec/lascool4.html [Broken]
    Last edited by a moderator: May 6, 2017
  4. Jul 14, 2014 #3
    Ok I looked at that material covering Optical Molasses. Before any advanced optical tweezing can be done at the individual atom level it must be possible to accurately detect an atoms position and frequency. One technique that could get atoms to a state where you can accurately measure these values that is covered in the material from the above link is using a MOT (Magnetic Optical Trap). This along with evaporative cooling could bring a sample of atoms to the state of a BEC (Bose-Einstein Condensate). Once in a BEC state the atoms move slow enough to get accurate measurements on them.

    Using a single MOT is effective for getting a single tightly packed group of millions of atoms into the BEC state. The goal however is not to get a group of millions of atoms into the BEC state, but to single out an individual atom into the BEC state.

    Maybe a system of multiple MOTs can be used in several consecutive steps to get to a point where a single atom is brought to the BEC state.

    Here's an example of steps I am considering for getting a single atom to the BEC state.

    1. First a MOT brings a group of millions of atoms to the BEC. (Just as it is currently done.)

    2. Accurate measurements of the position and frequency of a section of the BEC are taken and lasers tuned to the right frequency are applied to the targeted section of the BEC to strip it from the rest of the BEC.

    3. The stripped off section of the BEC is moved into a separate MOT using optical tweezers. This second MOT brings this smaller sample of atoms into a BEC state.

    4. Steps 2 and 3 are repeated over and over again until a sample of only one atom is brought to the BEC state.

    Once single atoms are in a BEC state it might be possible to move them together with other individual atoms to for desired meta-material bonds.

    One major barrier to deal with when getting these atoms to bond is to compensate for inter-atomic forces such as Van der Waals force.

    Does anyone have any suggestions relating to my idea for using multiple MOTs to get a single atom to a BEC state or anything else I am talking about?
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