Enhanced insulating state and diluted Ir4+ spin orders in Ir-vacant Sr2Ir1−xO4 systems Huiting Yu, Shengli Liu, Bin Li, Haiyun Wang, Jie Cheng and Z. H. Wang EPL, 120 2 (2017) 27007 Published online: 17 January 2018 DOI: 10.1209/0295-5075/120/27007