All Questions
Tagged with specific-reference quantum-information
13
questions
4
votes
2
answers
836
views
Which paper introduced the concept of the "Bloch sphere"?
Everyone loves Bloch sphere, but which paper of Bloch was it introduced? The Wikipedia article on Bloch sphere (here), as of 17/May/2021 links to this paper of Bloch “Nuclear Induction” but it doesn’t ...
- 3,612
1
vote
2
answers
187
views
When was Electromagnetically Induced Transparency first introduced?
The oldest paper I know regarding this topic was published in 1997 by Stephen E. Harris. But I am not sure if he is the first to introduce this idea. Could you tell me when and by who did introduce ...
- 2,737
4
votes
1
answer
1k
views
Why does the BB84 paper "Quantum cryptography: Public key distribution and coin tossing" have a 'withdrawn' status?
The original paper proposing quantum key distribution protocol (now known as BB84):
Charles H. Bennett, Gilles Brassard, Quantum cryptography: Public key distribution and coin tossing
seems to have <...
- 6,480
1
vote
0
answers
41
views
Thermodynamics of binary symmetric channels
I am reading this very interesting paper:
http://m.iopscience.iop.org/1751-8121/41/40/402002/pdf/1751-8121_41_40_402002.pdf about thermodynamics of channels in information theory.
More generally, ...
- 819
1
vote
1
answer
135
views
Low rank entangled states
In some recent works, I got the information that low rank mixed states need not be bound entangled. In particular, for the system $3\otimes 3$ there is no bound entangled states. Can anyone tell me ...
- 65
2
votes
0
answers
60
views
What is known about the trace of two copies of a channel / four copies of an isometry
Let $\mathcal{E} : \mathcal{L}(A) \to \mathcal{L}(B)$ be a completely positive trace preserving map. By the Choi–Jamiołkowski isomorphism there is an isometry $J : A \to B \otimes C$ such that $\...
- 809
6
votes
0
answers
130
views
Known properties of a specific class of quantum states
Recently, I have been studying a quantum protocol for the "Hidden Matching" problem that makes use of states that can be expressed as
$$|\psi\rangle=\frac{1}{\sqrt{n}}\sum_{i=1}^n (-1)^{x_i}|i\rangle$$...
- 1,354
3
votes
1
answer
347
views
How can you distinguish between projections of quantum states?
Consider this problem in quantum cryptography:
We have two pure states $\phi_1,\phi_2$ as input and constants $0 \leq \alpha <\beta \leq 1 $, where "Yes instances" are those for which $$\left|\...
2
votes
0
answers
221
views
Looking for description of Helstrom's measurement
I hope someone can help me find the page or chapter where Helstrom discusses his famous measurement for distinguishing between two mixtures in the textbook Quantum Detection and Estimation Theory.
...
7
votes
1
answer
327
views
States diagonal in the tensor product of Bell states.
Bell-diagonal states are 2-qubit states that are diagonal in the Bell basis. Since those states lie in $\mathbb{C}^{2} \otimes \mathbb{C}^{2}$, the Peres-Horodecki criterion is a sufficient condition ...
Alessandro Cosentino
10
votes
1
answer
135
views
Functional relations for Kochen-Specker proofs
Many proofs of the Kochen-Specker theorem use some form of the following argument (from Mermin's "Simple Unified Form for the major No-Hidden-Variables Theorems" )
[I]f some functional relation
$$...
MHoward
9
votes
1
answer
113
views
Many body quantum states analyzed as probabilistic sequences
Measurements of consecutive sites in a many body qudit system (e.q. a spin chain) can be interpreted as generating a probabilistic sequence of numbers $X_1 X_2 X_3 \ldots$, where $X_i\in \{0,1,\ldots,...
- 6,480
8
votes
1
answer
958
views
Is microcausality *necessary* for no-signaling?
There are proofs in the literature that QFT including microcausality is sufficient for it not to be possible to send signals by making quantum mechanical measurements associated with regions of space-...
- 9,948