153 citations · 350 across the 9 of their papers we have counts for
5 papers · 1 filter
Quantum key distribution secure against the efficiency loophole
Xiongfeng Ma, Tobias Moroder, Norbert Lütkenhaus
An efficiency-loophole-free quantum key distribution (QKD) scheme is proposed, which involves no hardware change but a modification in the data post-processing step. The scheme app…
Iterations of nonlinear entanglement witnesses
Tobias Moroder, Otfried Gühne, Norbert Lütkenhaus
We describe a generic way to improve a given linear entanglement witness by a quadratic, nonlinear term. This method can be iterated, leading to a whole sequence of nonlinear witne…
Squashing Models for Optical Measurements in Quantum Communication
Normand J. Beaudry, Tobias Moroder, Norbert Lütkenhaus
Measurements with photodetectors necessarily need to be described in the infinite dimensional Fock space of one or several modes. For some measurements a model has been postulated…
Truncated su(2) moment problem for spin and polarization states
Tobias Moroder, Michael Keyl, Norbert Lütkenhaus
We address the problem whether a given set of expectation values is compatible with the first and second moments of the generic spin operators of a system with total spin j. Those…
Effect of detector dead-times on the security evaluation of differential-phase-shift quantum key distribution against sequential attacks
Marcos Curty, Kiyoshi Tamaki, Tobias Moroder
We investigate limitations imposed by detector dead-times on the performance of sequential attacks against a differential-phase-shift (DPS) quantum key distribution (QKD) protocol…