Conference PaperQTROJAN: A Circuit Backdoor Against Quantum Neural NetworksChu, Cheng; Jiang, Lei; Swany, Martin; Chen, FanWe propose a circuit-level backdoor attack, QTrojan, against Quantum Neural Networks (QNNs) in this paper. QTrojan is implemented by a few quantum gates inserted into the variational quantum circuit of the victim QNN. QTrojan is much stealthier than a prior Data-Poisoning-based Backdoor Attack (DPBA) since it does not embed any trigger in the inputs of the victim QNN or require access to original training datasets. Compared to a DPBA, QTrojan improves the clean data accuracy by 21% and the attack success rate by 19.9%.2023-06-0410418392IEEE International Conference on Acoustics, Speech and Signal Processing1 to 5https://doi.org/10.1109/ICASSP49357.2023.100962931908992National Science Foundation