Speakers
Description
A. Bombardi [1], N. Qureshi [2], A. Vibhakar [1], K. Beauvois [3], R. Scatena [1], F. Carneiro [1], C. J. Won [4] and S.-W. Cheong [5]
[1] Diamond Light Source, Harwell Science and Innovation Campus Didcot OX11 0DE, Oxfordshire, UK
[2] Institut Laue-Langevin, 71 avenue des Martyrs, CS 20156, 38042 Grenoble Cedex 9, France
[3] Université Grenoble Alpes, CEA, IRIG, MEM, MDN, 38000 Grenoble, France
[4] Laboratory for Pohang Emergent Materials and Max Planck POSTECH Center for Complex Phase Materials, Pohang Univ. of Science and Technology, Dept. Phys., Pohang, Korea
[5] Rutgers Center for Emergent Materials and Department of Physics and Astronomy,
Rutgers University, Piscataway, NJ, 08854, USA
ABSTRACT
The chiral nature of our immediate environment is obvious to us structurally and functionally, and it seems to be a key ingredient of life, yet it remains one of the most elusive properties to understand and investigate at the atomic length scale.
X-rays measure structural chirality via the interference of the anomalous scattering factor. This provides a tiny variation in the measured intensity, usually sufficient to distinguish between different enantiomers, whereas both non-resonant and resonant magnetic scattering can be used to assess inversion domains in non collinear magnetic structure via the helicity of the probe, see [1] and references therein. The case of neutrons is similar, with polarized neutrons able to assess magnetic chirality and inversion domains [1], whereas the tiny relativistic Schwinger term is the only cross section term to measure the structural chirality [1].
Here, we present a combined X-ray and polarized neutron scattering study on chiral, polar and magnetoelectric compound NiCo2TeO6[2,3]. This system adopts a structural arrangement derived from the corundum R3c of Al2O3, but the introduction of Co and Te at the Al site breaks the inversion and the c-glide symmetry, generating a ferri-chiral structural arrangements, with often both chirality present in the same crystal.
Using a similar methodology to the one adopted in the case of Ba3NbFe3Si2O14 [1], we determine the relation between the magnetic and structural chirality in this system.
A clear theoretical framework of the microscopic interactions driving the chirality of NiCo2TeO6 is still missing, but our experimental results provide a sound foundation to understand the origin of this phenomenon and to future application of the magnetoelectric properties of this system.
REFERENCES
1. N. Qureshi et al. Phys. Rev. B 102, 054417 (2020).
2. X. Wang et al. APL Mater. 3, 076105 (2015).
3. N. Qureshi et al. to be submitted to Phys Rev B
