Experimental Quantum Cryptography with Qutrits

Author(s): S. Gröblacher, T. Jennewein, A. Vaziri, G. Weihs, A. Zeilinger

Journal: New Journal of Physics

Volume: 8

Page(s): 75

Year: 2006

DOI Number: 10.1088/1367-2630/8/5/075

Link: Link to publication


We produce two identical keys using, for the first time, entangled

trinary quantum systems (qutrits) for quantum key distribution. The advantage

of qutrits over the normally used binary quantum systems is an increased

coding density and a higher security margin. The qutrits are encoded into the

orbital angular momentum of photons, namely Laguerre–Gaussian modes with

azimuthal index l + 1, 0 and-1, respectively. The orbital angular momentum

is controlled with phase holograms. In an Ekert-type protocol the violation of

a three-dimensional Bell inequality verifies the security of the generated keys.

A key is obtained with a qutrit error rate of approximately 10%.

Note: http://arxiv.org/abs/quant-ph/0511163

File: Link to PDF

Zeilinger Group Zeilinger Group , Aspelmeyer Group