Semidefinite programs are convex optimization problems involving a linear objective
function and a domain of positive-semidefinite matrices. Over the past two decades, they …

Consider a sequential process in which each step outputs a system A i and updates a side
information register E. We prove that if this process satisfies a natural “non-signalling” …

The goal of quantum key distribution (QKD) is to establish a secure key between two parties
connected by an insecure quantum channel. To use a QKD protocol in practice, one has to …

The matrix logarithm, when applied to Hermitian positive definite matrices, is concave with
respect to the positive semidefinite order. This operator concavity property leads to …

Magic-state distillation (or nonstabilizer state manipulation) is a crucial component in the
leading approaches to realizing scalable, fault-tolerant, and universal quantum computation …

Having a distance measure between quantum states satisfying the right properties is of
fundamental importance in all areas of quantum information. In this work, we present a …

The generalized amplitude-dam** channel (GADC) is one of the sources of noise in
superconducting-circuit-based quantum computing. It can be viewed as the qubit analog of …

This paper presents a comprehensive exploration of semi-definite programming (SDP)
techniques within the context of quantum information. It examines the mathematical …

Distance measures between quantum states like the trace distance and the fidelity can
naturally be defined by optimizing a classical distance measure over all measurement …

The von Neumann entropy of a quantum state is a central concept in physics and
information theory, having a number of compelling physical interpretations. There is a …