Motifs of periodic modulations are encountered in a variety of natural systems. In strongly correlated electron systems, such behaviour has typically been associated with competition between short- and long-range interactions, for example, between exchange and dipole–dipole interactions in the case of ferromagnetic thin films. In this talk I will present our recent discovery that spin-stripe textures may develop also in antiferromagnets, where long-range dipole–dipole magnetic interactions are absent. In particular, a comprehensive analysis of magnetic susceptibility, high-field magnetization, specific-heat and neutron diffraction measurements unveils beta-TeVO4 as a nearly perfect realization of a frustrated (zigzag) ferromagnetic spin-1/2 chain. A narrow spin-stripe phase has been found at elevated magnetic fields that develop due to weak frustrated short-range interchain exchange interactions, possibly assisted by the symmetry-allowed electric polarization. This concept provides an alternative route for the stripe formation in strongly correlated electron systems.
B.04 Guest lecture
In this talk I will present our recent discovery that spin-stripe textures may develop also in antiferromagnets, where long-range dipole–dipole magnetic interactions are absent. In particular, a comprehensive analysis of magnetic susceptibility, high-field magnetization, specific-heat and neutron diffraction measurements unveils beta-TeVO4 as a nearly perfect realization of a frustrated (zigzag) ferromagnetic spin-1/2 chain. A narrow spin-stripe phase has been found at elevated magnetic fields that develop due to weak frustrated short-range interchain exchange interactions, possibly assisted by the symmetry-allowed electric polarization. This concept provides an alternative route for the stripe formation in strongly correlated electron systems.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 29195047In this talk I will present our neutron diffraction and muon spin relaxation results, which show that incommensurate amplitude-modulated magnetic long-range order is accompanied by spin fluctuations, persisting at lowest accessible temperatures. In our study we focus on FeTe2O5Br and beta-TeVO4, where the magnetic exchange network consists of weakly coupled spin chains. The observed behavior appears to be a more general feature of spin chains, which thus offer a well-defined framework to study the coexistence of long-range magnetic order and persistent spin dynamics.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 2754660In this invited lecture I presented a correlation between magnetic amplitude modulation and persistent spin dynamics. This is a rare phenomenon that we have observed in the amplitude modulated magnetic ground state of the FeTe2O5Br system. Based on our experimental results, we also managed to explain the coexistence of long-range magnetic order and persistent spin dynamics, which are generally considered to be mutually exclusive. Moreover, we find that for the observed response Fe-O-Te-O-Fe-exchange paths are vital, as they form a frustrated magnetic network.
B.04 Guest lecture
COBISS.SI-ID: 27092007In this lecture I also presented the link between the magnetic amplitude modulation and persistent spin dynamics, where I stressed the importance of Fe-O-Te-O-Fe exchange pathways, forming a frustrated magnetic network. The latter is crucial for the realization of complex amplitude-modulated magnetic structure, which coexists with both persistent spin dynamics as well as the electric polarization.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 26993447