English
Related papers

Related papers: An operational link between MUBs and SICs

200 papers

Examples of symmetric informationally complete positive operator valued measures (SIC-POVMs) have been constructed in every dimension less than or equal to 67. However, it remains an open question whether they exist in all finite…

Quantum Physics · Physics 2011-02-28 D. M. Appleby , Steven T. Flammia , Christopher A. Fuchs

In this paper, we prove that the existence of a complete set of mutually unbiased bases (MUBs) in N-dimensional Hilbert space implies the existence of a complete set of mutually orthogonal Latin squares (MOLSs) of order N. In particular, we…

Quantum Physics · Physics 2026-01-26 Stefan Joka

Akin to the idea of complete sets of Mutually Unbiased Bases for prime dimensional Hilbert spaces, $\mathcal{H}_d$, we study its analogue for a $d$ dimensional subspace of $M (d,\mathbb{C})$, i.e. Mutually Unbiased Unitary Bases (MUUBs)…

Quantum Physics · Physics 2019-06-11 Rinie N. M. Nasir , Jesni Shamsul Shaari , Stefano Mancini

We present a detailed computational and algebraic study of Mutually Unbiased Bases (MUBs) in finite-dimensional Hilbert spaces, with a particular focus on dimensions 2, 3, 4, and the challenging case of 6. Starting from the Hadamard-phase…

Quantum Physics · Physics 2026-04-03 Jean-Christophe Pain

We present a new approach to the problem of mutually unbiased bases (MUBs), based on positive definite functions on the unitary group. The method provides a new proof of the fact that there are at most $d+1$ MUBs in ${\mathbb C}^d$. It may…

Quantum Physics · Physics 2016-12-30 Mihail N. Kolountzakis , Máté Matolcsi , Mihály Weiner

Complete sets of mutually unbiased bases are only known to exist in prime-power dimensions. We will describe a few approaches to the problem proving the (non)-existence of four mutually unbiased bases in dimension 6. These will include the…

Mathematical Physics · Physics 2010-12-15 Guo Chuan Thiang

We address the problem of constructing positive operator-valued measures (POVMs) in finite dimension $n$ consisting of $n^2$ operators of rank one which have an inner product close to uniform. This is motivated by the related question of…

Quantum Physics · Physics 2023-11-27 Andreas Klappenecker , Martin Roetteler , Igor Shparlinski , Arne Winterhof

Mutually unbiased bases (MUB) are an elusive discrete structure in Hilbert spaces. Many (complete sets of) MUB are group covariant, but little is known whether they can be sharply covariant in the sense that the generating groups can have…

Quantum Physics · Physics 2015-03-03 Huangjun Zhu

In this paper, we explore the concept of Mutually Unbiased Bases (MUBs) in discrete quantum systems. It is known that for dimensions $d$ that are powers of prime numbers, there exists a set of up to $d+1$ bases that form an MUB set.…

Mutually unbiased bases (MUBs) are highly symmetric bases on complex Hilbert spaces, and the corresponding rank-1 projective measurements are ubiquitous in quantum information theory. In this work, we study a recently introduced…

Quantum Physics · Physics 2023-10-16 Máté Farkas , Jędrzej Kaniewski , Ashwin Nayak

In quantum mechanics, mutually unbiased bases (MUBs) represent orthonormal bases that are as "far apart" as possible, and their classification reveals rich underlying geometric structure. Given a complex inner product space, we construct…

Mathematical Physics · Physics 2025-08-22 Amit Te'eni , Eliahu Cohen

We consider the existence in arbitrary finite dimensions d of a POVM comprised of d^2 rank-one operators all of whose operator inner products are equal. Such a set is called a ``symmetric, informationally complete'' POVM (SIC-POVM) and is…

Quantum Physics · Physics 2007-07-16 Joseph M. Renes , Robin Blume-Kohout , A. J. Scott , Carlton M. Caves

Excluding the existence of four MUBs in $\bbC^6$ is an open problem in quantum information. We investigate the number of product vectors in the set of four mutually unbiased bases (MUBs) in dimension six, by assuming that the set exists and…

Quantum Physics · Physics 2018-07-13 Lin Chen , Li Yu

In this thesis we study symmetric structures in Hilbert spaces known as symmetric informationally complete positive operator-valued measures (SIC-POVMs), mutually unbiased bases (MUBs), and MUB-balanced states. Our tools include symmetries…

Quantum Physics · Physics 2015-08-12 Hoan Bui Dang

The connection between maximal sets of mutually unbiased bases (MUBs) in a prime-power dimensional Hilbert space and finite phase-space geometries is well known. In this article we classify MUBs according to their degree of covariance with…

Mathematical Physics · Physics 2016-06-23 Claudio Carmeli , Jussi Schultz , Alessandro Toigo

Mutually Unbiased bases has various application in quantum information procession and coding theory. There can be maximum d + 1 MUBs in C^d and d/2 +1 MUBs in R^d. But , over R^d MUBs are known to be non existent when d is odd and for most…

Quantum Physics · Physics 2025-12-16 Ajeet Kumar , Uditanshu Sadual

Mutually unbiased bases correspond to highly useful pairs of measurements in quantum information theory. In the smallest composite dimension, six, it is known that between three and seven mutually unbiased bases exist, with a decades-old…

Quantum Physics · Physics 2022-08-17 Maria Prat Colomer , Luke Mortimer , Irénée Frérot , Máté Farkas , Antonio Acín

A set of mutually unbiased bases (MUBs) is said to be unextendible if there does not exist another basis that is unbiased with respect to the given set. Here, we prove the existence of smaller sets of MUBs in prime-squared dimensions…

Quantum Physics · Physics 2015-08-25 Vishakh Hegde , Prabha Mandayam

This note is a short elaboration of the conjecture of Saniga et al (J. Opt. B: Quantum Semiclass. 6 (2004) L19-L20) by regarding a set of mutually unbiased bases (MUBs) in a d-dimensional Hilbert space, d being a power of a prime, as an…

Quantum Physics · Physics 2015-06-26 Metod Saniga , Michel Planat

Mutually unbiased bases (MUB) are useful in a number of research areas. The symmetry of MUB is an elusive and interesting subject. A (complete set of) MUB in dimension $d$ is sharply covariant if it can be generated by a group of order…

Quantum Physics · Physics 2015-09-09 Huangjun Zhu