Phase transition in CsHSO$_4$ ferroelastic in a magnetic field

A magnetically induced deceleration of the initial stage of the isothermal phase transition of ferroelastic-superprotonic cesium hydrogen sulfate has been detected. The effect is observed in time dependences of the proton conductivity in an external magnetic field when the high-temperature phase of a single crystal is supercooled. At the same time, the magnetic field hardly affects the conductivity in the homogeneous superprotonic phase above the transition temperature. The observed phenomenon is probably related to the magnetic transformation of pinning centers, which reduces the mobility of phase interfaces.