> Professor Ebrahim Karimi, a member of uOttawa's Department of
> Physics and holder of the Canada Research Chair in Structured
> Light, and doctoral student Frédéric Bouchard observe the setup
> they used to clone the photons that transmit information, called
> qudits. Credit: University of Ottawa
>
>
> As we saw during the 2016 US election, protecting traditional computer
> systems, which use zeros and ones, from hackers is not a perfect
> science. Now consider the complex world of quantum computing, where
> bits of information can simultaneously hold multiple states beyond
> zero and one, and the potential threats become even trickier to
> tackle. Even so, researchers at the University of Ottawa have
> uncovered clues that could help administrators protect quantum
> computing networks from external attacks.
>
> "Our team has built the first high-dimensional quantum cloning machine
> capable of performing quantum hacking to intercept a secure quantum
> message," said University of Ottawa Department of Physics professor
> Ebrahim Karimi, who holds the Canada Research Chair in Structured
> Light. "Once we were able to analyze the results, we discovered some
> very important clues to help protect quantum computing networks
> against potential hacking threats."
>
> Quantum systems were believed to provide perfectly secure data
> transmission because until now, attempts to copy the transmitted
> information resulted in an altered or deteriorated version of the
> original information, thereby defeating the purpose of the initial
> hack. Traditional computing allows a hacker to simply copy and paste
> information and replicate it exactly, but this doesn't hold true in
> the quantum computing world, where attempts to copy quantum
> information-or qudits-result in what Karimi refers to as "bad" copies.
> Until now.
>
> For the first time, Professor Karimi's team was able to clone the
> photons that transmit information, namely the single carriers of light
> known as qubits, as well as quantum theory allows, meaning that the
> clones were almost exact replicas of the original information.
> However, in addition to undermining what was previously thought to be
> a perfect way of securely transmitting information, the researchers'
> analyses revealed promising clues into how to protect against such
> hacking.
>
> "What we found was that when larger amounts of quantum information are
> encoded on a single photon, the copies will get worse and hacking even
> simpler to detect," said Frédéric Bouchard, a University of Ottawa
> doctoral student and lead author of an open access publication that
> appeared this month in the renowned journal Science Advances. "We were
> also able to show that cloning attacks introduce specific, observable
> noises in a secure quantum communication channel. Ensuring photons
> contain the largest amount of information possible and monitoring
> these noises in a secure channel should help strengthen quantum
> computing networks against potential hacking threats."
>
> Karimi and his team hope that their quantum hacking efforts could be
> used to study quantum communication systems, or more generally to
> study how quantum information travels across quantum computer
> networks. To read their paper, visit the Science Advances website.
>
> More information: High-dimensional quantum cloning and applications to
> quantum hacking, Science Advances 03 Feb 2017, DOI:
> 10.1126/sciadv.1601915
>
> Provided by University of Ottawa
https://phys.org/news/2017-02-quantum-networks-hacking-threats.html
