Patent ID: 8311224

Claim:
A quantum cryptography authentication system comprising: an optical link having a first end and a second end; a sender connected to the first end of the optical link, the sender transmitting: a first optical pulse and a second optical pulse, the first optical pulse and the second optical pulse having a defined time delay therebetween; the first pulse modulated with a first authentication phase shift; the second pulse being modulated with phases selected from one basis of two non-orthogonal bases, and encoded with one of two orthogonal states within the one basis based on an information of the sender, the second pulse further modulated with a second authentication phase shift; a receiver connected to the second end of the optical link, the receiver comprising: a first polarization beam splitter receiving and splitting the first pulse into a third pulse and a fourth pulse, and the second pulse into a fifth pulse and a sixth pulse; the fourth pulse and the sixth pulse being sent to a first optical reference loop and modulated with the first authentication phase shift; the third pulse and the fifth pulse being sent to a first optical delay loop and modulated with the second authentication phase shift; a first coupler connected to the first optical reference loop and the first optical delay loop, the first coupler combining the third pulse, the fourth pulse, the fifth pulse and the sixth pulse; the third pulse and the sixth pulse arriving at the first coupler simultaneously; a first set of detectors receiving the combined third pulse and sixth pulse, and determining the one basis of the two non-orthogonal bases; and a second set of detectors receiving the combined third pulse and sixth pulse, and determining the one of the two orthogonal states within the basis and thereby decoding the information of the sender; wherein the third pulse and the fifth pulse are polarized orthogonally to the fourth pulse and the sixth pulse.