September 30, 2016
Published by Stephan Sponar
In the last decade, several universally valid forms of error-disturbance uncertainty relations were derived for completely general quantum measurements for arbitrary states. An optimal form for spin measurements for some pure states was established recently. However, the bound in his inequality is not stringent for mixed states. Masanao Ozawa derived a new bound tight in the corresponding mixed state case, which was tested by our group. We experimentally observed the attainability of the new bound. B. Demirel et al., Physical Review Letters 117, 140402 (2016)
July 13, 2015
Published by Stephan Sponar
Uncertainty relation in quantum information theory publish in PRL and relieved an Editor’s Suggestion! Information is a key quantity in science and plays a significant role in many economic sectors such as communication technologies, cryptography, or data storage. In quantum communication and information technology the transfer and encryption of information is studied. Sulyok et al., Phys. Rev. Lett. 115, 030401 (2015)
July 29, 2014
Published by Stephan Sponar
The Cheshire Cat featured in Lewis Caroll’s novel “Alice in Wonderland” is a remarkable creature: it disappears, leaving its grin behind. Can an object be separated from its properties? Denkmayr et al., Nat. Commun. 5, 4492 (2014)
January 16, 2012
Published by Stephan Sponar
Heisenberg’s uncertainty principle. is certainly one of the most famous foundations of quantum physics. According to this principle, not all properties of a quantum particle are determined with arbitrary accuracy. In the early days of quantum theory, this has often been justified by the notion that every measurement inevitably recoils the quantum particle, which disturbs the results of any further measurements. This, however, turns out to be an oversimplification. In our neutron polarimetric experiment different sources of quantum uncertainty could now be distinguished, validating theoretical results of an error-disturbance uncertainty relation proposed by Masanao Ozawa. Y. Hasegawa et al., Nature Physics 8, 185-189 (2012)