In materials with strong local Coulomb interactions, simple defects such as atomic
substitutions strongly affect both macroscopic and local properties of the system. A …

An overview of one-and two-dimensional quantum spin systems based on transition-metal
oxides and halides of current interest is given, such as spin-Peierls, spin-dimer …

The spin dynamics of an arbitrary localized impurity in an insulating two-dimensional
antiferromagnet, across the host transition from a paramagnet with a spin gap to a Néel …

We present the universal theory of arbitrary, localized impurities in a confining paramagnetic
state of two-dimensional antiferromagnets with global SU (2) spin symmetry. The energy gap …

We report a first-order phase transition between dimerized-antiferromagnetic and uniform-
antiferromagnetic phases in impurity-doped spin-Peierls (SP) cuprate Cu 1− x Mg x GeO 3 …

A positive muon spin rotation and relaxation (μ+ SR) experiment on [Ca 2 CoO 3] 0.62 [CoO
2](ie, Ca 3 Co 4 O 9, a layered thermoelectric cobaltite) indicates the existence of two …

Vacancy-ordered halide double perovskites hosting 4 d/5 d transition metals have emerged
as a distinct platform for investigating unconventional magnetism arising out of the interplay …

The nature of the magnetic transition of the Na-rich thermoelectric Na 0.75 CoO 2 at 22 K
was studied by positive muon-spin-rotation and relaxation (μ+ SR) spectroscopy, using a …

The antiferromagnetic (AF) nature of the normal spinel Co 3 O 4 with Néel temperature
(TN)= 30 K was investigated by means of positive muon spin rotation and relaxation (μ+ SR) …

We investigate the Néel temperature of Sr 2 CuO 3 as a function of the site dilution at the Cu
(S= 1∕ 2) sites with Pd (S= 0), utilizing the muon spin relaxation (μ SR) technique. The Néel …