Attacking a high-dimensional quantum key distribution system with wavelength-dependent beam splitter

Du Ge-Hai^{1, 2}, Li Hong-Wei^{1, 2, †}, Wang Yang^{1, 2}, Bao Wan-Su^{1, 2, ‡}

Relationship between quantum bit error rate and coupling ratios. For dimensions d = 2, 4, 8, 16 [panels (a)–(d)], only data points ( r 1 , r 2 ) satisfying Err value less than the maximal tolerable error rate (11%, 18.9%, 24.7%, 28.9%)^[44] can guarantee successful wavelength attack.