Structural, magnetic, and electronic evolution of the spin-ladder system BaFe$_2$S$_{3-x}$Se$_x$ with isoelectronic substitution

1School of Physics, Sun Yat-sen University, Guangzhou, Guangdong 510275, China 2Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA 3Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, USA 4Department of Physics, University of California, Berkeley, California 94720, USA 5Department of Physics and Astronomy, Rice University, Houston, TX 77005, USA 6NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA