Related papers: Single-shot Quantum State Merging
For a system randomly prepared in a number of quantum states, we present a lower bound for the distinguishability of the quantum states, that is, the success probability of determining the states in the form of entropy. When the states are…
Quantum key distribution allows two parties, traditionally known as Alice and Bob, to establish a secure random cryptographic key if, firstly, they have access to a quantum communication channel, and secondly, they can exchange classical…
Information about an unknown quantum state can be encoded in weak values of projectors belonging to a complete eigenbasis. We present a protocol that enables one party -- Bob -- to remotely determine the weak values corresponding to weak…
Quantum Communication is the art of transferring an unknown quantum state from one location, Alice, to a distant one, Bob. This is a non-trivial task because of the quantum no-cloning theorem which prevents one from merely using only…
Alice, Bob, and Eve share a pure quantum state. We introduce the notion of state degradability by asking whether the joint density of Alice and Eve can be transformed to the joint density of Alice and Bob by processing Eve's part through a…
Shannon in celebrated works had shown that n bits of shared key is necessary and sufficient to transmit n-bit classical information in an information-theoretically secure way. Ambainis, Mosca, Tapp and de Wolf in quant-ph/0003101 considered…
Quantum entanglement distillation protocols are LOCC protocols between Alice and Bob that convert imperfect EPR pairs, or, in general, partially entangled bipartite states into perfect or near-perfect EPR pairs. The classical communication…
A notion of asymmetric quantum dialogue (AQD) is introduced. Conventional protocols of quantum dialogue are essentially symmetric as both the users (Alice and Bob) can encode the same amount of classical information. In contrast, the scheme…
The problem of unambiguous state discrimination consists of determining which of a set of known quantum states a particular system is in. One is allowed to fail, but not to make a mistake. The optimal procedure is the one with the lowest…
Entanglement-based attacks, which are subtle and powerful, are usually believed to render quantum bit commitment insecure. We point out that the no-go argument leading to this view implicitly assumes the evidence-of-commitment to be a…
A set of $n$ pure quantum states is called antidististinguishable if there exists an $n$-outcome measurement that never outputs the outcome `$k$' on the $k$-th quantum state. We describe sets of quantum states for which any subset of three…
Covert communication is necessary when revealing the mere existence of a message leaks sensitive information to an attacker. Consider a network link where an authorized transmitter Jack sends packets to an authorized receiver Steve, and the…
We consider the problem of how to manipulate the entanglement properties of a general two-particle pure state, shared between Alice and Bob, by using only local operations at each end and classical communication between Alice and Bob. A…
We provide explicit schemes for quantum information splitting (QIS) of real or equatorial two qubit states among two parties, through the five particle cluster and Brown states respectively. The schemes introduced are neither fully…
There are no ``unknown quantum states.'' It's a contradiction in terms. Moreover, Alice and Bob are only inanimate objects. They know nothing. What is teleported instantaneously from one system (Alice) to another system (Bob) is the…
After carrying out a protocol for quantum key agreement over a noisy quantum channel, the parties Alice and Bob must process the raw key in order to end up with identical keys about which the adversary has virtually no information. In…
The quantum channel subject to local interaction with two-level environment is studied. The two-level environment is regarded as a quantum bit (qubit) as well as a pair of particles owned by Alice and Bob. The amount of entanglement…
Implementations of many quantum communication protocols require sources of photon pairs. However, optimization of the properties of these photons for specific applications is an open problem. We theoretically demonstrate the possibility of…
A mixed quantum state shared between two parties is said to be distillable if, by means of a protocol involving only local quantum operations and classical communication, the two parties can transform some number of copies of that state…
From the perspective of quantum information theory, a system so simple as one restricted to just two nonorthogonal states can be surprisingly rich in physics. In this paper, we explore the extent of this statement through a review of three…