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We investigate the quantum-memory-assisted entropic uncertainty relation (QMA-EUR) in a Heisenberg XYZ mixed-spin (1/2, 1) model. Coupling strength, Dzyaloshinskii-Moriya (DM) interaction and inhomogeneous magnetic field, respectively, contributing to QMA-EUR by a thermal entanglement in the hybrid-spin model are studied in detail. Furthermore, we compare the uncertainty of the bipartite hybrid model with those of qubit-qubit and qutrit-qutrit systems. Meanwhile, the effects of local PT-symmetric operation and weak measurement on the steering of entropic uncertainty are analyzed. We find that the local PT-symmetric operation can reduce the entropic uncertainty, and the entropic uncertainty can also be decreased by weak measurement reversal.  相似文献   
3.
In this paper,we consider a possible modification of the de Sitter and anti-de Sitter space for the extended uncertainty principle.For the modified anti-de Sitter model we discuss the representation and wave functions of the momentum operator for a one-dimensional box problem.Also,we consider modified Snyder and anti-Snyder models for the generalized uncertainty principle.Then,we assume the Hamiltonian with different potential and solve the Heisenberg algebra for the modified(anti)-de Sitter and(anti)-Snyder models in both position and in the momentum space.  相似文献   
4.
《Physics letters. A》2020,384(2):126061
In this paper, we proposed an unidimensional continuous-variable quantum key distribution (CV-QKD) protocol with discrete modulation, which waives the necessity in one of the quadrature modulations and further simplified the implementation of the CV-QKD protocol. On the basis of the Heisenberg uncertainty relation, we analyze the boundary between the unphysical and physical region. Besides, we utilize a novel proof approach to achieve a lower bound valid of transmission distance. This scheme shows an available method to further simplified the implementation of the QKD.  相似文献   
5.
《Physics letters. A》2020,384(1):126037
In bosonic fields, Gaussian states, which consist of a rather wide family of states including coherent states, squeezed states, thermal states, etc., have many classical-like features, and are usually defined from the mathematical perspective in terms of characteristic functions. It is well known that some special Gaussian states, such as coherent states, are minimum uncertainty states for the conventional Heisenberg uncertainty relation involving canonical pair of position and momentum observables. A natural question arises as whether all Gaussian states can be characterized as minimum uncertainty states. In this work, we show that indeed Gaussian states coincide with minimum uncertainty states for an information-theoretic refinement of the conventional uncertainty relation established in Luo (2005) [40]. This characterization puts Gaussian states on a novel basis of physical significance.  相似文献   
6.
Motivated by the well-established phase derivative embedded technique, this study devotes to sharper uncertainty principles related to the Lp-norm type of uncertainty product, giving rise to two kinds of uncertainty inequalities that improve the classical result through providing tighter lower bounds. The conditions that truly reach these better estimates are obtained. Examples and simulations are carried out to verify the correctness of the derived results, and finally, possible applications in time-frequency analysis are also given.  相似文献   
7.
采用电感耦合等离子体质谱法(ICP-MS)测定食用植物油中铅(Pb)、总砷(As)含量,对测定结果的不确定度进行评定。利用ICP-MS,采用标准加入法测定食用植物油中Pb,As含量,分析测定过程中不确定度来源,包括样品称量、定容、前处理、溶液中Pb和As浓度、重复性测量等引入的不确定度,计算合成不确定度。结果表明,Pb含量为(0.0228±0.013) mg/kg,k=2;As含量为(0.00785±0.0045) mg/kg,k=2。该方法的不确定度主要来源于样品溶液中的Pb,As浓度,评定得到的不确定度可为正确评价测定结果提供科学依据。  相似文献   
8.
Local quantum uncertainty and interferometric power were introduced by Girolami et al. as geometric quantifiers of quantum correlations. The aim of the present paper is to discuss their properties in a unified manner by means of the metric adjusted skew information defined by Hansen.  相似文献   
9.
This article contributes to the development of methods for shape optimization under uncertainties, associated with the flow conditions, based on intrusive Polynomial Chaos Expansion (iPCE) and continuous adjoint. The iPCE to the Navier–Stokes equations for laminar flows of incompressible fluids is developed to compute statistical moments of the Quantity of Interest which are, then, compared with those obtained through the Monte Carlo method. The optimization is carried out using a continuous adjoint-enabled, gradient-based loop. Two different formulations for the continuous adjoint to the iPCE PDEs are derived, programmed, and verified. Intrusive PCE methods for the computation of the statistical moments require mathematical development, derivation of a new system of governing equations and their numerical solution. The development is presented for a chaos order of two and two uncertain variables and can be used as a guide to those willing to extend this development to a different set of uncertain variables or chaos order. The developed method and software, programmed in OpenFOAM, is applied to two optimization problems pertaining to the flow around isolated airfoils with uncertain farfield conditions.  相似文献   
10.
研制了海藻糖国家标准样品。以食品级海藻糖粗品为原料,纯化制备海藻糖,采用红外光谱(IR)、质谱和核磁共振谱(NMR)以及单晶衍射等方法进行结构确证。样品分装成400瓶后,采用离子色谱法进行均匀性、稳定性检验和定值分析。从样品中随机抽取15瓶进行均匀性检验,经F检验表明,在95%的置信区间范围内,样品均匀性良好。在40℃下,经过24个月稳定性考察,结果表明样品稳定性良好。标准样品经国内8家具有分析资质的实验室进行协同定值,并评定了定值结果的不确定度,海藻糖标准样品定值结果为99.72%,扩展不确定度为0.26%(k=1.96)。该标准样品达到国家标准样品的技术要求,可用于有关海藻糖的方法校正和质量控制。  相似文献   
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