Unsharp measurements, joint measurability and classical distributions for some qudits

التفاصيل البيبلوغرافية
العنوان: Unsharp measurements, joint measurability and classical distributions for some qudits
المؤلفون: Rao, H S Smitha, Sirsi, Swarnamala, Bharath, Karthik
سنة النشر: 2020
المجموعة: Quantum Physics
مصطلحات موضوعية: Quantum Physics
الوصف: Classicality associated with joint measurability of operators manifests through a valid classical joint probability distribution on measurement outcomes. For qudits in dimension $n$, where $n$ is prime or power of prime, we present a method to construct unsharp versions of projective measurement operators which results in a geometric description of the set of quantum states for which the operators engender a classical joint probability distribution, and are jointly measurable. Specifically, within the setting of a generalised Bloch sphere in $n^2-1$ dimensions, we establish that the constructed operators are jointly measurable for states given by a family of concentric spheres inscribed within a regular polyhedron, which represents states that lead to classical probability distributions. Our construction establishes a novel perspective on links between joint measurability and optimal measurement strategies associated with Mutually Unbiased Bases (MUBs), and formulates a necessary condition for the long-standing open problem of existence of MUBs in dimension $n=6$.
Comment: 5 pages, 1 figure
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2004.05547
رقم الأكسشن: edsarx.2004.05547
قاعدة البيانات: arXiv