Twist-bend nematic liquid crystals in high magnetic fields

TL;DR

This study investigates the effects of high magnetic fields on the twist-bend nematic phase in liquid crystals, revealing how magnetic fields influence phase transitions and optical textures.

Contribution

It provides the first magneto-optic measurements on Ntb materials and proposes a mechanism for magnetic field effects on phase behavior and stripe textures.

Findings

Magnetic fields inhibit optical stripe textures in Ntb phases.

A 25T magnetic field lowers the N-Ntb phase transition temperature by nearly 1°C.

Proposed a Helfrich-Hurault-type mechanism for stripe formation.

Abstract

We present magneto-optic measurements on two materials that form the recently discovered twist-bend nematic (Ntb) phase. This intriguing state of matter represents a new fluid phase that is orientationally anisotropic in three directions and also exhibits translational order with periodicity several times larger than the molecular size. NTB materials may also spontaneously form a visible, macroscopic stripe texture. We show that the optical stripe texture can be persistently inhibited by a magnetic field, and a 25T external magnetic field depresses the N-Ntb phase transition temperature by almost 1 degree C. We propose a quantitative mechanism to account for this shift and suggest a Helfrich-Hurault-type mechanism for the optical stripe formation.