This is one of the things most scientists envy physicists for. I would estimate 95% of those papers are copyrighted, and yet, since we have had this structure for so long, no publisher tries to pursue us for sharing our work with the public for free.
I don't know about other fields of physics, but in astro, most of the data is free access as well. I personally work only with public data and I'm paid to do it. A string attached to governmental funding from the Euro or NSF is usually a mandated free access database.
Sometimes I take for granted the fact that my morning ritual involves reading every publication in my field from the day before, without license. And then I download some free data, program in my free languages, write in my free latex editor, and then publish my work for free in a place anyone can read it. It's utopic.
I don't know about other fields of physics, but in astro, most of the data is free access as well. I personally work only with public data and I'm paid to do it. A string attached to governmental funding from the Euro or NSF is usually a mandated free access database.
Sometimes I take for granted the fact that my morning ritual involves reading every publication in my field from the day before, without license. And then I download some free data, program in my free languages, write in my free latex editor, and then publish my work for free in a place anyone can read it. It's utopic.
edit: two archives with a lot of different missions data for example: http://irsa.ipac.caltech.edu/frontpage/ https://archive.stsci.edu