Beamtime checklist |
At least 2 months before:
|
Sample preparation |
You can request sample holders to be shipped to your home institution ahead of time; contact beamline staff and provide a FedEx number. ARPES: Please contact staff ASAP to discuss sample preparation. At the moment, our chamber only offers the following capabilities:
RSXS: The current set-up uses a kappa geometry with a horizontal scattering plane. Note that a very limited number of diffraction peaks can be accessed in the soft x-ray range (E<3keV). This coupled with the fact that conversion to the standard 4-C nomenclature (phi, chi, theta and 2theta) is non-intuitive makes experimental planning crucial. Please consider pre-aligning your sample to speed-up alignment, and contact staff if to make sure the q-range you want to study is accessible. |
Sample cooling |
LHe: Both endstations (RSXS and ARPES) are equipped with open cycle cryostats. Liquid He cost is the users' responsibility:
Proper cooling is critical for the success of soft x-ray ARPES experiment because of the destructive effect of electron-phonon scattering on the coherent ARPES signal (see https://www.nature.com/articles/nmat3089). If you are unsure about the temperature required to perform ARPES measurement on your samples, we recommend setting-up an account anyway, in case LHe turns out to be necessary. There are very few materials for which the electronic structure can be resolved at liquid Nitrogen temperatures or higher. LN2: Liquid Nitrogen is provided free of charge. |
Before coming |
If you don't have a user badge or if your user badge has expired, please make sure to notify the user office of your arrival by checking-in on the APS User Portal; by doing so, a gate pass will be requested on your behalf. Remember to bring your ID and immigration documents (even if you have a badge). Access to the Argonne National Lab is extremely restricted: failure to check in and/or present appropriate documentation can lead to hours long wait or even access denial. Finally, please make sure to completed your trainings before coming to the beamline; this included Sector 29 orientation. Note that any missing training might delay your experiment since no work (including mounting samples) will be allowed until all experimenters have completed their required training. Upon arriving, make sure to stop by the APS user office during business hours (M-F, 8am-5pm) to get your badge activated. |