Extracting partition function zeros from Fukui-Todo simulations

The Fukui-Todo algorithm is an important element of the array of simulational approaches to tackling critical phenomena. The partition-function-zero approach is of fundamental importance to understanding them and a precise tool to measuring their properties. However, because the Fukui-Todo algorithm bypasses sample-by-sample energy computation, zeros cannot easily be harnessed through the energy distribution. Here this obstacle is overcome by a novel reweighting technique and zero-detection protocol. The efficacy of the approach is demonstrated in simple iconic models which feature transitions of both first and second order.