Yu-Jie Qian

Detecting quantum states faithfully is the basis of quantum cryptography. Unfortunately, detector control attacks allow eavesdroppers to manipulate the click of detectors, leading to information leakage and security breaches. Here we propose a control-resistant detection method to close the loophole. Our method is to use a signal sorter to detect the eavesdropping attacks and an analytical tool to quantify them. The results indicate that, without optical component changes and performance loss, the eavesdropping can not only be perceived but its information leakage can also be tightly estimated.