Usually the details are covered by the same journal where the paper is published under the title of supplementary information. If it is not available you can directly contact the authors from the contact details given on the paper. Both the ways works very well.
Dear all, some journal use the experimental details in a separate file with a specific DOI. It is named 'Supplement file'. It is mentionned in the first page mother file. Generally it is free downloadable. My Regards