Magnetocapacitance and spin fluctuations in the geometrically frustrated magnets R2Ti2O7 (R=rareearth)

Abstract

Magnetocapacitance has been measured for the geometrically frustrated magnets $R_2{\mathrm{Ti}}_2{\mathrm{O}}_7$ $(R=\mathrm{rare}\mathrm{}\mathrm{earth}).\mathrm{}$ The temperature dependence of magnetocapacitance, which largely deviates from the square of magnetization, indicates the evolution of strong ferromagnetic $(R=\mathrm{Ho})$ or antiferromagnetic $(R=\mathrm{Gd})$ fluctuation at low temperatures. This result demonstrates that the measurement of mangetocapacitance is a powerful technique to detect the magnetic fluctuation of exotic magnets.