English
Related papers

Related papers: Entropic uncertainty relations and locking: tight …

200 papers

We provide a construction of sets of (d/2+1) mutually unbiased bases (MUBs) in dimensions d=4,8 using maximal commuting classes of Pauli operators. We show that these incomplete sets cannot be extended further using the operators of the…

Quantum Physics · Physics 2014-02-05 Prabha Mandayam , Somshubhro Bandyopadhyay , Markus Grassl , William K. Wootters

Uncertainty relations express the fundamental incompatibility of certain observables in quantum mechanics. Far from just being puzzling constraints on our ability to know the state of a quantum system, uncertainty relations are at the heart…

Quantum Physics · Physics 2012-08-30 Omar Fawzi

From a practical perspective it is advantageous to develop methods that verify entanglement in quantum states with as few measurements as possible. In this paper we investigate the minimal number of mutually unbiased bases (MUBs) needed to…

Quantum Physics · Physics 2023-03-14 Joonwoo Bae , Anindita Bera , Dariusz Chruściński , Beatrix C. Hiesmayr , Daniel McNulty

We propose a family of lower bounds for concurrence in quantum systems using mutually unbiased measurements, which prove more effective in entanglement estimation compared to existing methods. Through analytical and numerical examples, we…

Quantum Physics · Physics 2025-04-22 Yu Lu , Meng Su , Zhong-Xi Shen , Hong-Xing Wu , Shao-Ming Fei , Zhi-Xi Wang

Given two orthornormal bases A and B, the basic form of the entropic uncertainty principle is stated in terms of the sum of the Shannon entropies of the probabilities of measuring A and B onto a given quantum state. State independent lower…

Quantum Physics · Physics 2020-10-28 Paolo Giorda

The resource theoretic measure of quantum coherence is basis dependent, and the amount of coherence contained in a state is different in different bases. We obtained analytical solutions for the maximum coherence by optimizing the reference…

Quantum Physics · Physics 2017-11-13 Ming-Liang Hu , Shu-Qian Shen , Heng Fan

Entropic uncertainty relations are underpinning to compute the quantitative security bound in quantum cryptographic applications, such as quantum random number generation (QRNG) and quantum key distribution (QKD). All security proofs derive…

Quantum Physics · Physics 2023-01-23 Minu J. Bae

Mutually unbiased bases (MUBs) constitute the canonical example of incompatible quantum measurements. One standard application of MUBs is the task known as quantum random access code (QRAC), in which classical information is encoded in a…

Quantum Physics · Physics 2020-04-02 Máté Farkas , Jędrzej Kaniewski

The study of Mutually Unbiased Bases continues to be developed vigorously, and presents several challenges in the Quantum Information Theory. Two orthonormal bases in $\mathbb C^d, B {and} B'$ are said mutually unbiased if $\forall b\in B,…

Quantum Physics · Physics 2009-08-12 M. Combescure

We derive two quantum uncertainty relations for position and momentum coarse-grained measurements. Building on previous results, we first improve the lower bound for uncertainty relations using the Renyi entropy, particularly in the case of…

Quantum Physics · Physics 2012-11-06 Łukasz Rudnicki , Stephen P. Walborn , Fabricio Toscano

Uncertainty relations play a central role in quantum mechanics. Entropic uncertainty relations in particular have gained significant importance within quantum information, providing the foundation for the security of many quantum…

Quantum Physics · Physics 2011-05-02 Stephanie Wehner , Andreas Winter

We investigate the fine-grained uncertainty relations for qubit system by measurements corresponding respectively to two and three spin operators. Then we derive the general bound for a combination of two probabilities of projective…

Quantum Physics · Physics 2021-09-24 Li-Hang Ren , Heng Fan

Finite tight frames are interesting in various topics including questions of quantum information. Each complex tight frame leads to a resolution of the identity in the Hilbert space. Symmetric informationally complete measurements are a…

Quantum Physics · Physics 2023-08-21 Alexey E. Rastegin

A tight information-theoretic measurement uncertainty relation is experimentally tested with neutron spin-1/2 qubits. The noise associated to the measurement of an observable is defined via conditional Shannon entropies and a tradeoff…

Quantum Physics · Physics 2019-02-12 Bülent Demirel , Stephan Sponar , Alastair A. Abbott , Cyril Branciard , Yuji Hasegawa

In the course of the last decades entropic uncertainty relations have attracted much attention not only due to their fundamental role as manifestation of non-classicality of quantum mechanics, but also as major tools for applications of…

Quantum Physics · Physics 2020-05-13 Andreas Ketterer , Otfried Gühne

We investigate the interplay between mutual unbiasedness and product bases for multiple qudits of possibly different dimensions. A product state of such a system is shown to be mutually unbiased to a product basis only if each of its…

Quantum Physics · Physics 2016-03-18 Daniel McNulty , Bogdan Pammer , Stefan Weigert

In standard formulations of the uncertainty principle, two fundamental features are typically cast as impossibility statements: two noncommuting observables cannot in general both be sharply defined (for the same state), nor can they be…

Quantum Physics · Physics 2018-06-08 Tom Bullock , Paul Busch

Tight bounds for several symmetric divergence measures are derived in terms of the total variation distance. It is shown that each of these bounds is attained by a pair of 2 or 3-element probability distributions. An application of these…

Information Theory · Computer Science 2016-11-17 Igal Sason

We present a systematic method to introduce free parameters in sets of mutually unbiased bases. In particular, we demonstrate that any set of m real mutually unbiased bases in dimension N>2 admits the introduction of (m-1)N/2 free…

Quantum Physics · Physics 2016-01-19 Dardo Goyeneche , Santiago Gomez

We consider the mismatched measurements in the BB84 quantum key distribution protocol, in which measuring bases are different from transmitting bases. We give a lower bound on the amount of a secret key that can be extracted from the…

Quantum Physics · Physics 2008-10-17 Ryutaroh Matsumoto , Shun Watanabe
‹ Prev 1 4 5 6 7 8 10 Next ›