How to wipe unused RAM in Windows 10?

Background: I’m trying to get as much security as possible. I have my hard drive encrypted with BitLocker, but I got worried about leaking something through RAM. Precisely, if someone gets to my laptop when it’s turned on but locked, they could still retrieve some data from it’s RAM by some cold boot procedure. As far as I know, encrypting RAM is not possible on Windows, so I thought of wiping the unused portion of it in order to limit what might get leaked.

Question: Is there a Windows command (or feature, or utility) that would wipe unused portion of RAM (without shutting down of course)?