Those backslashes are likely not really part of the folder name, but inserted by the Terminal program to escape spaces in the folder name. As others have suggest, renaming the folder to something simplier is the easiest way forward.
Or, try this: Replace your use of dir with:
This press the Tab key. Use tab-completion to drill down to the desired folder, then close the string.
I suspect you'll send up with an assignment like this (some line wrapping inserted by MATLAB Answers):
srcFiles=dir('/Users/andromache/Desktop/Research/data/other/180319_114103_A1 20X PL FL
Later, don't use strcat, but fullfile to create the filename:
filename = fullfile(srcFiles(i).folder, srcFiles(i).name)
Hope that helps