English
Related papers

Related papers: Quantum Potato Chips

200 papers

A linear map of qudit tomogram onto qubit tomogram (qubit portrait) is proposed as a characteristics of the qudit state. Using the qubit portrait method the Bell inequalities for two qubits and two qutrits are discussed in framework of…

Quantum Physics · Physics 2007-05-23 V. N. Chernega , V. I. Man'ko

While quantum state tomography (QST) remains the gold standard for benchmarking and verifying quantum devices, it requires an exponentially large number of measurements and classical computational resources for generic quantum many-body…

Quantum Physics · Physics 2025-11-19 Zhen Qin , Casey Jameson , Alireza Goldar , Michael B. Wakin , Zhexuan Gong , Zhihui Zhu

We investigate the quantum numbers of the pentaquark states $\textrm{P}_{\textrm{c}}^{+}$, which are composed of four (three flavors) quarks and an antiquark, by analyzing their inherent nodal structure in this paper. Assuming that the four…

High Energy Physics - Phenomenology · Physics 2021-09-22 Chong-yao Chen , Muyang Chen , Yu-xin Liu

A complex projective $t$-design is a configuration of vectors which is ``evenly distributed'' on a sphere in the sense that sampling uniformly from it reproduces the moments of Haar measure up to order $2t$. We show that the set of all…

Quantum Physics · Physics 2015-10-12 Richard Kueng , David Gross

Quantum hypothesis testing (QHT) provides an effective method to discriminate between two quantum states using a two-outcome positive operator-valued measure (POVM). Two types of decision errors in a QHT can occur. In this paper we focus on…

Quantum Physics · Physics 2023-07-13 Yi Shen , Carlo Maria Scandolo , Lin Chen

Usually, the three-tangle of a tripartite pure state of qubits can be directly measured with the simultaneous preparation of a not-less-than-four-fold copy of the state. We show that the exact genuine tripartite entanglement for…

Quantum Physics · Physics 2016-04-20 Chang-shui Yu , Bao-qing Guo , Si-ren Yang

To reconstruct a mixed or pure quantum state of a spin s is possible through coherent states: its density matrix is fixed by the probabilities to measure the value s along 4s(s+1) appropriately chosen directions in space. Thus, after…

Quantum Physics · Physics 2007-05-23 Stefan Weigert

We discuss a procedure of measurement followed by the reproduction of the quantum state of a three-level optical system - a frequency- and spatially degenerate two-photon field. The method of statistical estimation of the quantum state…

For pure symmetric 3-qubit states there are only three algebraically independent entanglement measures; one choice is the pairwise concurrence $\mathcal C$, the 3-tangle $\tau$, and the Kempe invariant $\kappa$. Using a canonical form for…

Quantum Physics · Physics 2017-12-13 Alexander Meill , David A. Meyer

With any state of a multipartite quantum system its separability polytope is associated. This is an algebro-topological object (non-trivial only for mixed states) which captures the localisation of entanglement of the state. Particular…

Quantum Physics · Physics 2015-06-26 Roman R. Zapatrin

In the usual tomography of multipartite entangled quantum states one assumes that the measurement devices used in the laboratory are under perfect control of the experimenter. In this paper, using the so-called SWAP concept introduced…

Quantum Physics · Physics 2014-11-05 Karoly F. Pal , Tamas Vertesi , Miguel Navascues

Quantum state tomography aims to determine the quantum state of a system from measured data and is an essential tool for quantum information science. When dealing with continuous variable quantum states of light, tomography is often done by…

Quantum Physics · Physics 2018-08-24 J. L. E. Silva , S. Glancy , H. M. Vasconcelos

We introduce and experimentally demonstrate a technique for performing quantum state tomography on multiple-qubit states despite incomplete knowledge about the unitary operations used to change the measurement basis. Given unitary…

We give an explicit expression for the geometric measure of entanglement for three qubit states that are linear combinations of four orthogonal product states. It turns out that the geometric measure for these states has three different…

Quantum Physics · Physics 2008-09-03 Levon Tamaryan , DaeKil Park , Jin-Woo Son , Sayatnova Tamaryan

Milz and Strunz ({\it J. Phys. A}: {\bf{48}} [2015] 035306) recently studied the probabilities that two-qubit and qubit-qutrit states, randomly generated with respect to Hilbert-Schmidt (Euclidean/flat) measure, are separable. They…

Quantum Physics · Physics 2016-06-06 Paul B. Slater

Generalized quantum measurements (also known as POVMs) are of great importance in quantum information and quantum foundations, but often difficult to perform. We present an experimental approach which can in principle be used to perform…

Given an ensemble of qubits, which we are told consists of a mixture of two pure states, one with probability $\eta_{0}$ and one with probability $\eta_{1}$, we want to find a POVM that will discriminate between the two states by measuring…

Quantum Physics · Physics 2020-11-11 Mark Hillery

As a possible physical realization of a quantum information processor, a system with stacked self-assembled InAs quantum dots buried in GaAs in adjacent to the channel of a spin field-effect transistor has been proposed. In this system,…

Mesoscale and Nanoscale Physics · Physics 2009-03-19 Kazuya Yuasa , Kosuke Okano , Hiromichi Nakazato , Saori Kashiwada , Kanji Yoh

We formulate a discrete two-state stochastic process with elementary rules that give rise to Born statistics and reproduce the probabilities from the Schr\"odinger equation under an associated Hamiltonian matrix, which we identify. We…

Quantum Physics · Physics 2023-09-19 Themis Matsoukas

We extend quantum state tomography with minimal cumulative disturbance, first investigated in [arXiv:2406.18370], to arbitrary finite-dimensional pure states. A learner sequentially receives fresh copies of an unknown pure state, chooses a…

Quantum Physics · Physics 2026-05-12 Josep Lumbreras , Marco Tomamichel