English
Related papers

Related papers: Two-Qubit Separability Probabilities: A Concise Fo…

200 papers

I report the existence of exactly one non-trivial solution to the equation $i(A,B)+i(A,\neg B)+i(\neg A,B)+i(\neg A,\neg B)= 0$, where $i(A,B)=\log\frac{P(A\text{ and }B)}{P(A)P(B)}$, and $P(A)$ is the probability of the proposition $A$.…

Quantum Physics · Physics 2025-04-08 R. O'Flanagan

The problems of Hadamard quantum coin flipping in n-trials and related generalized Fibonacci sequences of numbers were introduced in [1]. It was shown that for an arbitrary number of repeated consecutive states, probabilities are determined…

Quantum Physics · Physics 2021-10-27 Oktay K Pashaev

Quantum tomography is a widely applicable method for reconstructing unknown quantum states and processes. However, its applications in quantum technologies usually also require estimating the difference between prepared and target quantum…

Quantum Physics · Physics 2024-03-20 D. O. Norkin , E. O. Kiktenko , A. K. Fedorov

We analytically derive the bit-string probability distributions of subsystems of random pure states and depolarized random states using the Dirichlet distribution. We identify the exact Beta distribution as the universal statistical law of…

Quantum Physics · Physics 2026-02-24 Sangchul Oh

Digital computers store information in the form of bits that can take on one of two values 0 and 1, while quantum computers are based on qubits that are described by a complex wavefunction, whose squared magnitude gives the probability of…

Emerging Technologies · Computer Science 2021-10-14 Jan Kaiser , Supriyo Datta

The concept of entanglement and separability of quantum states is relevant for several fields in physics. Still, there is a lack of effective operational methods to characterise these features. We propose a method to certify quantum…

Quantum Physics · Physics 2024-03-06 Ties-A. Ohst , Xiao-Dong Yu , Otfried Gühne , H. Chau Nguyen

We propose an algorithm which proves a given bipartite quantum state to be separable in a finite number of steps. Our approach is based on the search for a decomposition via a countable subset of product states, which is dense within all…

Quantum Physics · Physics 2009-11-10 Florian Hulpke , Dagmar Bruss

The quantum guesswork quantifies the minimum number of queries needed to guess the state of a quantum ensemble if one is allowed to query only one state at a time. Previous approaches to the computation of the guesswork were based on…

Quantum Physics · Physics 2023-08-28 Michele Dall'Arno , Francesco Buscemi , Takeshi Koshiba

We obtain a collection of necessary (sufficient) conditions for a bipartite system of qubits to be separable (entangled), which are based on the Landau-Pollak formulation of the uncertainty principle. These conditions are tested, and…

Quantum Physics · Physics 2009-11-11 Julio I. de Vicente , Jorge Sánchez-Ruiz

We demonstrate that the task of determining an unknown quantum state can be accomplished efficiently by making a sequential measurement of two observables $\hat{A}$ and $\hat{B}$, provided that the two observables are chosen in such a way…

Quantum Physics · Physics 2013-10-22 Antonio Di Lorenzo

As it is well known, every bipartite $2\otimes 2$ density matrix can be obtained from Bell decomposable states via local quantum operations and classical communications (LQCC). Using this fact, the Lewenstein-Sanpera decomposition of an…

Quantum Physics · Physics 2007-05-23 S. J. Akhtarshenas , M. A. Jafarizadeh

In this paper we propose a product space reformulation to transform monotone inclusions described by finitely many operators on a Hilbert space into equivalent two-operator problems. Our approach relies on Pierra's classical reformulation…

Optimization and Control · Mathematics 2022-03-02 Rubén Campoy

We show that the bipartite separability of a pure qubit state hinges critically on the combinatorial structure of its computational-basis support. Using Boolean cube geometry, we introduce a taxonomy that distinguishes support-guaranteed…

General Physics · Physics 2026-01-23 Szymon Łukaszyk

We report the implementation of Grover's quantum search algorithm in the scalable system of trapped atomic ion quantum bits. Any one of four possible states of a two-qubit memory is marked, and following a single query of the search space,…

Quantum Physics · Physics 2009-11-11 K. -A. Brickman , P. C. Haljan , P. J. Lee , M. Acton , L. Deslauriers , C. Monroe

We develop an approach where the quantum system states and quantum observables are described as in classical statistical mechanics -- the states are identified with probability distributions and observables, with random variables. An…

Quantum Physics · Physics 2019-04-23 Vladimir N. Chernega , Olga V. Man'ko , Vladimir I. Man'ko

We analyze the set of two-qubit states from which a secret key can be extracted by single-copy measurements plus classical processing of the outcomes. We introduce a key distillation protocol and give the corresponding necessary and…

Quantum Physics · Physics 2016-08-16 A. Acín , J. Bae , E. Bagan , M. Baig , Ll. Masanes , R. Muñoz-Tapia

We distinguish six classes of families of locally equivalent states in a straightforward scheme for classifying all 2-q-bit states; four of the classes consist of two subclasses each. The simple criteria that we stated recently for checking…

Quantum Physics · Physics 2015-06-26 Berthold-Georg Englert , Nasser Metwally

Drawing on various notions from theoretical computer science, we present a novel numerical approach, motivated by the notion of algorithmic probability, to the problem of approximating the Kolmogorov-Chaitin complexity of short strings. The…

Information Theory · Computer Science 2015-03-13 Fernando Soler-Toscano , Hector Zenil , Jean-Paul Delahaye , Nicolas Gauvrit

Given integers n $\geq$ m, let Sep(n,m) be the set of separable states on the Hilbert space $\mathbb{C}^n \otimes \mathbb{C}^m$. It is well-known that for (n,m)=(3,2) the set of separable states has a simple description using semidefinite…

Quantum Physics · Physics 2019-05-08 Hamza Fawzi

In this paper, the binary random packing fraction of similar particles with size ratios ranging from unity to well over 2 is studied. The classic excluded volume model for spherocylinders and cylinders proposed by Onsager [1] is revisited…

Other Condensed Matter · Physics 2024-06-28 H. J. H. Brouwers