Hope this helps. This is a link to the Flight Standardization Board Report from the FAA for a Phenom 100 and 300 which is a single pilot airplane. If you look in the pilot type section, you will see that a pilot with a single pilot type may utilize an appropriately rated SIC if desired.
FSIMS Document Viewer
If you would like to see the board reports for other aircraft, type in "flight standardization board report CE525" and you will get the info on CJ type ratings. and the CE525 part was just an example.
If you don't want to look it up for yourself, I have and so for I've checked the 510, 525, and EMB-500 and 505 series and each says that a single pilot type may utilize an SIC.