English
Related papers

Related papers: Multi-Bloch Vector Representation of the Qutrit

200 papers

We study quantum tomography based on a stochastic continuous-time measurement record obtained from a probe field collectively interacting with an ensemble of identically prepared systems. In comparison to previous studies, we consider here…

Quantum Physics · Physics 2014-10-01 Robert L. Cook , Carlos A. Riofrío , Ivan H. Deutsch

We propose a probabilistic quantum protocol to realize a nonlinear transformation of qutrit states, which by iterative applications on ensembles can be used to distinguish two types of pure states. The protocol involves single-qutrit and…

Quantum Physics · Physics 2018-11-20 P. V. Pyshkin , A. Gábris , O. Kálmán , I. Jex , T. Kiss

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

We show that the Quantum State Distinguishability (QSD), which is a QSZK-complete problem, and the Quantum Circuit Distinguishability (QCD), which is a QIP-complete problem, can be solved by the verifier who can perform only single-qubit…

Quantum Physics · Physics 2016-07-05 Tomoyuki Morimae

Quantum information refers to the distinctive information-processing properties of quantum systems, which arise when information is stored in or retrieved from nonorthogonal quantum states. More information is required to prepare an…

Quantum Physics · Physics 2007-05-23 Carlton M. Caves , Christopher A. Fuchs

We aim to explore a more efficient way to simulate few-body dynamics on quantum computers. Instead of mapping the second quantization of the system Hamiltonian to qubit Pauli gates representation via the Jordan-Wigner transform, we propose…

Quantum Physics · Physics 2025-09-09 Peng Guo , Jaime Park , Frank X. Lee

The well studied quantum optical Schr\"{o}dinger cat state is a superposition of two distinguishable states, with quantum coherence between these macroscopically distinguishable states being of foundational and, in the context of…

Quantum Physics · Physics 2019-06-12 Namrata Shukla , Naeem Akhtar , Barry C. Sanders

For pure states, the quantum Berry curvature was well studied. However, the quantum curvature for mixed states has received less attention. From the concept of symmetric logarithmic derivative, we introduce a mixed-state quantum curvature…

Quantum Physics · Physics 2025-11-21 Xiaoguang Wang , Xiao-Ming Lu , Yunbo Zhang , Libin Fu , Shu Chen

Quantum states are the key mathematical objects in quantum theory. It is therefore surprising that physicists have been unable to agree on what a quantum state truly represents. One possibility is that a pure quantum state corresponds…

Quantum Physics · Physics 2015-03-31 Matthew F. Pusey , Jonathan Barrett , Terry Rudolph

We study the norms of the Bloch vectors for arbitrary $n$-partite quantum states. A tight upper bound of the norms is derived for $n$-partite systems with different individual dimensions. These upper bounds are used to deal with the…

Quantum Physics · Physics 2020-08-07 Wen Xu , Chuan-Jie Zhu , Zhu-Jun Zheng , Shao-Ming Fei

The aim of this paper is to introduce a new graphic representation of quantum states by means of a specific application: the analysis of two models of quantum copying machines. The graphic representation by diagrams of states offers a clear…

Quantum Physics · Physics 2007-05-23 Sara Felloni , Giuliano Strini

The concept of qudit (a d-level system) cluster state is proposed by generalizing the qubit cluster state (Phys. Rev. Lett. \textbf{86}, 910 (2001)) according to the finite dimensional representations of quantum plane algebra. We…

Quantum Physics · Physics 2009-11-10 D. L. Zhou , B. Zeng , Z. Xu , C. P. Sun

We obtain the optimal scheme for estimating unknown qubit mixed states when an arbitrary number N of identically prepared copies is available. We discuss the case of states in the whole Bloch sphere as well as the restricted situation where…

Quantum Physics · Physics 2009-11-11 E. Bagan , M. A. Ballester , R. D. Gill , A. Monras , R. Munoz-Tapia

We present a necessary and sufficient condition for three qutrit density matrices to be the one-particle reduced density matrices of a pure three-qutrit quantum state. The condition consists of seven classes of inequalities satisfied by the…

Quantum Physics · Physics 2007-05-23 Atsushi Higuchi

It is shown that generic N-party pure quantum states (with equidimensional subsystems) are uniquely determined by their reduced states of just over half the parties; in other words, all the information in almost all N-party pure states is…

Quantum Physics · Physics 2009-11-10 Nick S. Jones , Noah Linden

Entanglement is one of the key resources required for quantum computation, so experimentally creating and measuring entangled states is of crucial importance in the various physical implementations of a quantum computer. In superconducting…

In this study the determinant of the average quadratic error matrix is used as the measure of state estimation efficiency. This quantity is easily computable in some cases, so it gives us a reasonable tool to find optimal measurement setup…

Quantum Physics · Physics 2012-01-10 Denes Petz , Laszlo Ruppert

Recently quantum tomography has been proposed as a fundamental tool for prototyping a few qubit quantum device. It allows the complete reconstruction of the state produced from a given input into the device. From this reconstructed density…

Quantum Physics · Physics 2009-11-07 R. T. Thew , K. Nemoto , A. G. White , W. J. Munro

We consider the problem of determining the state of a quantum system given one or more readings of the expectation value of an observable. The system is assumed to be a finite dimensional quantum control system for which we can influence…

Quantum Physics · Physics 2009-11-10 Domenico D'Alessandro

Each platonic solid defines a single-qubit positive operator valued measure (POVM) by interpreting its vertices as points on the Bloch sphere. We construct simple circuits for implementing this kind of measurements and other simple types of…

Quantum Physics · Physics 2007-05-23 Thomas Decker , Dominik Janzing , Thomas Beth