scholarly journals Measuring dimensionality and purity of high-dimensional entangled states

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Isaac Nape ◽  
Valeria Rodríguez-Fajardo ◽  
Feng Zhu ◽  
Hsiao-Chih Huang ◽  
Jonathan Leach ◽  
...  
Keyword(s):  
Quantum Systems ◽  
High Dimensional ◽  
Entangled States ◽  
Acquisition Time ◽  
Quantitative Measurements ◽  
Conditional Measurement ◽  
Wide Range ◽  
Data Acquisition Time ◽  
Projective Measurements ◽  
Measurement Approach

AbstractHigh-dimensional entangled states are promising candidates for increasing the security and encoding capacity of quantum systems. While it is possible to witness and set bounds for the entanglement, precisely quantifying the dimensionality and purity in a fast and accurate manner remains an open challenge. Here, we report an approach that simultaneously returns the dimensionality and purity of high-dimensional entangled states by simple projective measurements. We show that the outcome of a conditional measurement returns a visibility that scales monotonically with state dimensionality and purity, allowing for quantitative measurements for general photonic quantum systems. We illustrate our method using two separate bases, the orbital angular momentum and pixels bases, and quantify the state dimensionality by a variety of definitions over a wide range of noise levels, highlighting its usefulness in practical situations. Importantly, the number of measurements needed in our approach scale linearly with dimensions, reducing data acquisition time significantly. Our technique provides a simple, fast and direct measurement approach.

TWO-PHOTON HIGH-DIMENSIONAL SPATIAL ENTANGLEMENT: THEORY AND EXPERIMENT

2006 ◽  
Vol 20 (01) ◽  
pp. 1-23 ◽  
Author(s):  
LEONARDO NEVES ◽  
G. LIMA ◽  
J. G. AGUIRRE GÓMEZ ◽  
C. H. MONKEN ◽  
C. SAAVEDRA ◽  
...  
Keyword(s):  
Quantum Systems ◽  
High Dimensional ◽  
Entangled States ◽  
Type Ii ◽  
Opaque Screen ◽  
Two Photon ◽  
Parametric Down Conversion ◽  
Experimental Works ◽  
Maximally Entangled States ◽  
Down Conversion

We review recent theoretical and experimental works where are proposed and demonstrated how to use photon pairs created by spontaneous parametric down-conversion to generate entangled states of D-dimensional quantum systems, or qudits. This is the first demonstration of high-dimensional entanglement based on the intrinsic transverse momentum entanglement of the type-II down-converted photons. The qudit space is defined by an aperture made up of an opaque screen with D slits (paths), placed in the arms of the twin photons. By manipulating the pump beam profile we can prepare different entangled states of these possible paths. We focus our attention on an important case for applications in quantum information: the maximally entangled states. Experimental results for qudits with D=4 and D=8 are shown and measuring a two-photon conditional interference, we also demonstrate the nonclassical character of the correlations.

scholarly journals 360° IMAGES FOR UAV MULTISENSOR DATA FUSION: FIRST TESTS AND RESULTS

2019 ◽  
Vol XLII-2/W13 ◽  
pp. 227-234 ◽  
Author(s):  
A. Calantropio ◽  
F. Chiabrando ◽  
D. Einaudi ◽  
L. Teppati Losè
Keyword(s):  
Data Fusion ◽  
3D Models ◽  
Acquisition Time ◽  
Multisensor Data Fusion ◽  
Rapid Mapping ◽  
Wide Range ◽  
Aerial Vehicle ◽  
Data Acquisition Time ◽  
Spherical Images ◽  
Multisensor Data

<p><strong>Abstract.</strong> A relevant research topic in the photogrammetry field is related with experimenting, at different levels, data fusion and sensors integration, aiming at the development of rapid mapping systems, capable of quickly delivering accurate data, for a wide range of applications. The presented contribute aims at exploiting the potentialities of spherical images and videos acquired using a 360° camera mounted on board of a medium-sized Unmanned Aerial Vehicle (UAV). More specifically, the focus has been the development and testing of a rapid-mapping hybrid system, capable of fast acquisition of data from both the on-board sensors. The reduction of the data acquisition time has been, and still is, a hot topic faced by the researchers in the Geomatics community, especially linked to some hazardous operative scenarios, where the reduction of the time on the field is crucial for operators’ safety reasons (like in post-earthquake early damage assessment surveys).</p><p>After a deep analysis of the available scientific literature, it turned out that researchers have been more focused on terrestrial applications of these emerging sensors (360° cameras), and no significant studies for aerial application have been conducted yet. First of all, some laboratory tests have been carried out, in order to evaluate the metric accuracy of the 3D models generated using the employed 360° sensor; thereafter, a solution for acquiring spherical images from 360° camera mounted on a light UAV has been designed. Problems and issues have been addressed and discussed, and results and improvements are, at the end of the paper, evaluated and proposed.</p>

scholarly journals Development of a Simplified Radiometric Calibration Framework for Water-Based and Rapid Deployment Unmanned Aerial System (UAS) Operations

2020 ◽  
Author(s):  
Christopher M. Zarzar ◽  
Padmanava Dash ◽  
Jamie L. Dyer ◽  
Robert Moorhead ◽  
Lee Hathcock
Keyword(s):  
River Estuary ◽  
Pearl River Estuary ◽  
Pearl River ◽  
Acquisition Time ◽  
Radiometric Calibration ◽  
Calibration Technique ◽  
Wide Range ◽  
Data Acquisition Time ◽  
Rapid Deployment ◽  
Calibration Equations

The current study sets out to develop an empirical line method (ELM) radiometric calibration framework for reducing atmospheric contributions in UAS imagery and for producing scaled remote sensing reflectance imagery. Using a MicaSense RedEdge camera flown on a custom-built octocopter, the research reported herein finds that atmospheric contributions have an important impact on UAS imagery. Data collected over the Lower Pearl River Estuary in Mississippi during five week-long missions covering a wide range of environmental conditions was used to develop and test a simplified ELM radiometric calibration framework designed specifically for the reduction of atmospheric contributions to UAS imagery in studies with limited site accessibility or data acquisition time constraints. The framework was effective in reducing atmospheric and other external contributions to UAS imagery. Unique to the proposed radiometric calibration framework is the radiance to reflectance conversion conducted externally from the calibration equations which allows for the normalization of illumination independent from the time of UAS image acquisition and from the time of calibration equations development. This paper presents the simplified ELM radiometric calibration framework that can be used as a time-effective calibration technique to reduce errors in the UAS imagery.

scholarly journals Matrix Product State Simulations of Non-Equilibrium Steady States and Transient Heat Flows in the Two-Bath Spin-Boson Model at Finite Temperatures

Entropy ◽  
2021 ◽  
Vol 23 (1) ◽  
pp. 77
Author(s):  
Angus J. Dunnett ◽  
Alex W. Chin
Keyword(s):  
Finite Temperature ◽  
Open Quantum Systems ◽  
Quantum Systems ◽  
Steady States ◽  
Matrix Product ◽  
Open Quantum ◽  
Matrix Product State ◽  
Wide Range ◽  
Boson Model ◽  
Non Equilibrium

Simulating the non-perturbative and non-Markovian dynamics of open quantum systems is a very challenging many body problem, due to the need to evolve both the system and its environments on an equal footing. Tensor network and matrix product states (MPS) have emerged as powerful tools for open system models, but the numerical resources required to treat finite-temperature environments grow extremely rapidly and limit their applications. In this study we use time-dependent variational evolution of MPS to explore the striking theory of Tamascelli et al. (Phys. Rev. Lett. 2019, 123, 090402.) that shows how finite-temperature open dynamics can be obtained from zero temperature, i.e., pure wave function, simulations. Using this approach, we produce a benchmark dataset for the dynamics of the Ohmic spin-boson model across a wide range of coupling strengths and temperatures, and also present a detailed analysis of the numerical costs of simulating non-equilibrium steady states, such as those emerging from the non-perturbative coupling of a qubit to baths at different temperatures. Despite ever-growing resource requirements, we find that converged non-perturbative results can be obtained, and we discuss a number of recent ideas and numerical techniques that should allow wide application of MPS to complex open quantum systems.

A matrix realignment method for recognizing entanglement

2003 ◽  
Vol 3 (3) ◽  
pp. 193-202
Author(s):  
K. Chen ◽  
L.-A. Wu
Keyword(s):  
Kronecker Product ◽  
Singular Values ◽  
Quantum Systems ◽  
Entangled States ◽  
Approximation Technique ◽  
Separable State ◽  
Simple Method ◽  
Bipartite Quantum Systems ◽  
The Matrix ◽  
Degree Of Entanglement

Motivated by the Kronecker product approximation technique, we have developed a very simple method to assess the inseparability of bipartite quantum systems, which is based on a realigned matrix constructed from the density matrix. For any separable state, the sum of the singular values of the matrix should be less than or equal to $1$. This condition provides a very simple, computable necessary criterion for separability, and shows powerful ability to identify most bound entangled states discussed in the literature. As a byproduct of the criterion, we give an estimate for the degree of entanglement of the quantum state.

Measurement of carbonization region on leather cutting in CO2 and diode laser-based laser beam process

2021 ◽  
pp. 095440892110563
Author(s):  
S. Vasanth ◽  
T. Muthuramalingam
Keyword(s):  
Image Processing ◽  
Laser Beam ◽  
Diode Laser ◽  
Heat Affected Zone ◽  
Diode Lasers ◽  
Standard Procedure ◽  
Wide Range ◽  
Thermal Influence ◽  
Cutting Experiments ◽  
Measurement Approach

There is a quite wide range of animal leathers such as cow leather, sheep leather and buffalo leather used for leather garments and leather goods such as bags, wallets and other customized leather articles. The drawbacks of manual cutting can be eliminated by laser-based cutting. However, unwanted carbonization is happened owing to the higher thermal influence. There is no standard procedure or method available to measure the carbonization region on leather cutting. Diode lasers can process leather rapidly and efficiently. In the present work, an attempt was proposed to introduce the image processing-based measurement approach in leather cutting using CO2 laser and diode laser. The cutting experiments were performed on sheep leather with a thickness of 1 mm. It was found that the proposed can effectively measure the heat-affected zone (HAZ) of leather cutting. It has also been found that diode laser could produce lower HAZ than CO2 laser on leather cutting.

Experimental ladder proof of Hardy's nonlocality for high-dimensional quantum systems

2017 ◽  
Vol 96 (2) ◽  
Author(s):  
Lixiang Chen ◽  
Wuhong Zhang ◽  
Ziwen Wu ◽  
Jikang Wang ◽  
Robert Fickler ◽  
...  
Keyword(s):  
Quantum Systems ◽  
High Dimensional

scholarly journals Quantum computing and second quantization

2017 ◽  
Vol 26 (03) ◽  
pp. 1741006 ◽  
Author(s):  
Hanna Makaruk
Keyword(s):  
Quantum Computing ◽  
Approximate Method ◽  
Quantum Systems ◽  
General Idea ◽  
Entangled States ◽  
Quantum Computers ◽  
Second Quantization ◽  
Particle Arrangement ◽  
The Many

Quantum computers by their nature are many particle quantum systems. Both the many-particle arrangement and being quantum are necessary for the existence of the entangled states, which are responsible for the parallelism of the quantum computers. Second quantization is a very important approximate method of describing such systems. This lecture will present the general idea of the second quantization, and discuss shortly some of the most important formulations of second quantization.

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