Quantum computing: when ignorance is wanted

Artistic image of a homomorphic-encrypted quantum computation using a photonic quantum computer. Equinox Graphics, Universität Wien) - Quantum technologies for computers open up new concepts of preserving the privacy of input and output data of a computation. Scientists from the University of Vienna, the Singapore University of Technology and Design and the Polytechnic University of Milan have shown that optical quantum systems are not only particularly suitable for some quantum computations, but can also effectively encrypt the associated input and output data. This demonstration of a so-called quantum homomorphic encryption of a quantum computation has now been published in "NPJ Quantum Information". Quantum computers promise not only to outperform classical machines in certain important tasks, but also to maintain the privacy of data processing. The secure delegation of computations has been an increasingly important issue since the possibility of utilizing cloud computing and cloud networks. Of particular interest is the ability to exploit quantum technology that allows for unconditional security, meaning that no assumptions about the computational power of a potential adversary need to be made.