Magnetic field as a dynamic energy scale in quantum-critical CeCoIn${}_5$

Abstract

Whether magnetic field enters the quantum-critical dynamics as a competing energy scale in strange metals remains an open question. Using thermal impedance spectroscopy, we simultaneously measure the electronic specific heat and spin-relaxation dynamics of CeCoIn${}_5$. Both properties show scale invariance with temperature and magnetic field, where a single energy scale governs their crossover. Magnetic field thus competes directly with temperature to set the infrared cutoff, establishing it as a dynamic energy scale in the critical dynamics of this strange metal.

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