I host a Laravel application on Apache for Windows. I use the mod_authnz_sspi module and have my site configured to require SSPI authorization. This populates $_SERVER['PHP_AUTH_USER'] with the Windows username of the visitor. I check this value against known users who are allowed to log in with Windows username. If the user is allowed, they are automatically signed in.
# httpd.conf snippet
LoadModule authnz_sspi_module modules/mod_authnz_sspi.so
# httpd-vhosts.conf snippet
<Directory "foo">
Order allow,deny
Allow from all
#AuthName "SSPI Protected Place"
AuthType SSPI
SSPIAuth On
SSPIAuthoritative On
SSPIOfferBasic On
Require valid-user
</Directory>