Leditzky, Felix; Rouzé, Cambyse; Datta, Nilanjana (SpringerLetters in Mathematical Physics, 2016)
The $\alpha$-sandwiched Rényi divergence satisfies the data processing inequality, i.e. monotonicity under quantum operations, for $\alpha$ $\geq$ 1/2. In this article, we derive a necessary and sufficient algebraic condition ...