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Experimental detection of entanglement of an arbitrary state of a given bipartite system is crucial for exploring many areas of quantum information. But such a detection should be made in a device independent way if the preparation process…

Quantum Physics · Physics 2017-11-22 Arindam Mallick , Sibasish Ghosh

We discuss the cases where local decoherence selectively degrades one type of entanglement more than other types. A typical case is called state ordering change, in which two input states with different amounts of entanglement undergoes a…

Quantum Physics · Physics 2013-05-29 Yuma Kinoshita , Ryo Namiki , Takashi Yamamoto , Masato Koashi , Nobuyuki Imoto

It is a crucial feature of quantum mechanics that not all measurements are compatible with each other. However, if measurements suffer from noise they may lose their incompatibility. Here, we consider the effect of white noise and determine…

Quantum Physics · Physics 2026-01-30 Martin J. Renner

The bidirectional steerability between different-size subsystems is discussed for a single parameter accelerated qubit-qutrit system. The decoherence due to the mixing and acceleration parameters is investigated, where for the total system…

Quantum Physics · Physics 2022-03-02 M. Y. Abd-Rabbou , N. Metwally , M. M. A. Ahmed , A. -S. F. Obada

In any probabilistic theory, we may say a bipartite state on a composite system AB steers its marginal state (on, say, system B) if, for any decomposition of the marginal as a mixture, with probabilities p_i, of states b_i of B, there…

Quantum Physics · Physics 2010-03-05 Howard Barnum , Carl Phillipp Gaebler , Alexander Wilce

To determine whether a given multipartite quantum state is separable with respect to some partition we construct a family of entanglement measures R_m. This is done utilizing generalized concurrences as building blocks which are defined by…

Quantum Physics · Physics 2010-08-06 Tsubasa Ichikawa , Marcus Huber , Philipp Krammer , Beatrix C. Hiesmayr

Multistability, the coexistence of multiple stable states, is a cornerstone of nonlinear dynamical systems, governing their equilibrium, tunability, and emergent complexity. Recently, the concept of hidden multistability, where certain…

Chaotic Dynamics · Physics 2025-11-07 Kun Zhang , Qicheng Zhang , Shuaishuai Tong , Wenquan Wu , Xiling Feng , Chunyin Qiu

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

In the present work, we address the question of how bipartite steering violation takes place among multi-partite systems (where each sub-system have Hilbert space dimension restricted to two) based on the maximal violations of the bipartite…

Quantum metrology uses quantum states with no classical counterpart to measure a physical quantity with extraordinary sensitivity or precision. Most metrology schemes measure a single parameter of a dynamical process by probing it with a…

Quantum Physics · Physics 2014-11-11 Lee A. Rozema , Dylan H. Mahler , Robin Blume-Kohout , Aephraim M. Steinberg

The bidirectional steering between two accelerated partners sharing initially different classes of entangled states is discussed. Due to the decoherence, the steerability and its degree decrease either as the acceleration increases or the…

Quantum Physics · Physics 2025-07-25 M. Y. Abd-Rabbou , N. Metwally , M. M. A. Ahmed , A. -S. F. Obada

Predicting the outcomes of quantum measurements is a cornerstone of quantum information theory and a key resource for quantum technologies. Here, we introduce a comprehensive framework for quantifying the predictability of measurements on a…

Quantum Physics · Physics 2026-01-28 Dennis I. Martínez-Moreno , Miguel Castillo-Celeita , Diego G. Bussandri

We derive a fine-grained uncertainty relation for the measurement of two incompatible observables on a single quantum system of continuous variables, and show that continuous variable systems are more uncertain than discrete variable…

Quantum Physics · Physics 2015-10-19 Priyanka Chowdhury , Tanumoy Pramanik , Archan S. Majumdar

We consider entanglement detection for quantum key distribution systems that use two signal states and continuous variable measurements. This problem can be formulated as a separability problem in a qubit-mode system. To verify…

Quantum Physics · Physics 2007-05-23 Johannes Rigas , Otfried Gühne , Norbert Lütkenhaus

We derive steerability criteria applicable for both finite and infinite dimensional quantum systems using covariance matrices of local observables. We show that these criteria are useful to detect a wide range of entangled states…

Quantum Physics · Physics 2016-01-06 Se-Wan Ji , Jaehak Lee , Jiyong Park , Hyunchul Nha

Quantum steering, an intermediate quantum correlation lying between entanglement and nonlocality, has emerged as a critical quantum resource for a variety of quantum information processing tasks such as quantum key distribution and true…

Quantum Physics · Physics 2025-01-22 Yansa Lu , Zhihua Chen , Zhihao Ma , Shao-Ming Fei

We analyze the distinguishability norm on the states of a multi-partite system, defined by local measurements. Concretely, we show that the norm associated to a tensor product of sufficiently symmetric measurements is essentially equivalent…

Quantum Physics · Physics 2013-09-17 Cécilia Lancien , Andreas Winter

To gain an advantage, quantum technologies utilize phenomena particular to quantum mechanics. Two such phenomena are squeezing and entanglement. Having generated states that exhibit these features, verification of their generation with…

Quantum Physics · Physics 2021-06-02 Russell P Rundle

Entanglement is a fundamental feature of quantum mechanics, playing a crucial role in quantum information processing. However, classifying entangled states, particularly in the mixed-state regime, remains a challenging problem, especially…

Quantum instruments describe both the classical outcome and the updated state associated with a quantum measurement. We ask whether these processes can be simulated using only a natural subset of resources, namely projective measurements on…

Quantum Physics · Physics 2025-07-24 Shishir Khandelwal , Armin Tavakoli