Demonstration of a quantum controlled-NOT gate in the telecommunications band.
We present the first quantum controlled-not (cnot) gate realized using a fiber-based indistinguishable photon-pair source in the 1.55 microm telecommunications band. Using this free-space cnot gate, all four Bell states are produced and fully characterized by performing quantum-state tomography, demonstrating the gate's unambiguous entangling capability and high fidelity. Telecom-band operation makes this cnot gate particularly suitable for quantum-information-processing tasks that are at the interface of quantum communication and linear optical quantum computing.
Chen
Jun
J
Center for Photonic Communication and Computing, EECS Department, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3118, USA.
Altepeter
Joseph B
JB
Medic
Milja
M
Lee
Kim Fook
KF
Gokden
Burc
B
Hadfield
Robert H
RH
Nam
Sae Woo
SW
Kumar
Prem
P