Illuminate\Auth\Guard uses this method to log the user out:
/**
* Refresh the "remember me" token for the user.
*
* @param \Illuminate\Contracts\Auth\Authenticatable $user
* @return void
*/
protected function refreshRememberToken(UserContract $user)
{
$user->setRememberToken($token = Str::random(60));
$this->provider->updateRememberToken($user, $token);
}
I guess you could just reproduce those two lines of code with your own User object and they will be "logged out" as far as the server is considered, meaning the next request they send will fail the authenticated middleware if required.
If you also want to fire the logout event, here is how the same class does that:
$this->events->fire('auth.logout', [$user]);
So you can just use the global helper function event:
event('auth.logout', [$user]);