Field evolution of quantum critical and heavy Fermi-liquid components in the magnetization of the mixed valence compound beta-YbAlB4

Abstract

We present the high-precision magnetization data of the valence fluctuating heavy fermion superconductor $\beta$-YbAlB${}_4$ in a wide temperature range from 0.02 K to 320 K spanning four orders of magnitude. We made detailed analyses of the $T/B$ scaling of the magnetization, and firmly confirmed the unconventional zero-field quantum criticality (QC) without tuning. We examined other possible scaling relationship such as $T/(B-B_c{)}^{\delta }$ scaling, and confirmed that $\delta =1$ provides the best quality of the fit with an upper bound on the critical magnetic field $|B_c|<0.2$~mT. We further discuss the heavy Fermi-liquid component of the magnetization after subtracting the QC component estimated based on the $T/B$ scaling. The temperature dependence of the heavy Fermi-liquid component is found very similar to the magnetization of the polymorph $\alpha$-YbAlB${}_4$. In addition, the heavy Fermi-liquid component is suppressed in the magnetic field above $\sim$ 5 T as in $\alpha$-YbAlB${}_4$. This was also confirmed by the magnetization measurements up to $\sim 50$ T for both $\alpha$- and $\beta$-YbAlB${}_4$. Interestingly, the detailed analyses revealed that the only a part of $f$ electrons participates in the zero-field QC and the heavy fermion behavior. We also present a temperature - magnetic field phase diagram of \ybal to illustrate how the characteristic temperature and field scales evolves near the QC.

arXiv comment9 pages, 6 figures

References in corpus (21)

• Fermi-liquid instabilities at magnetic quantum phase transitions
• Quantum Criticality in Heavy Fermion Metals
• The break up of heavy electrons at a quantum critical point
• Magnetic-Field Induced Quantum Critical Point in YbRh${}_2$Si${}_2$
• Quantum critical state in a magnetic quasicrystal
• Quantum Criticality without Tuning in the Mixed Valence Compound beta-YbAlB4
• Quantum Valence Criticality as Origin of Unconventional Critical Phenomena
• Strong valence fluctuation in the quantum critical heavy fermion superconductor beta-YbAlB4: A hard x-ray photoemission study
• Magnetic-Field Dependence of the YbRh2Si2 Fermi Surface
• Interplay between Kondo suppression and Lifshitz transitions in YbRh${}_2$Si${}_2$ at high magnetic fields
• Layered Kondo lattice model for quantum critical beta-YbAlB4
• β-YbAlB4: a critical nodal metal
• Field-induced suppression of the heavy-fermion state in YbRh_2Si_2
• Robustness of Quantum Criticality of Valence Fluctuations
• Metamagnetism and Lifshitz Transitions in Models for Heavy Fermions
• Anisotropic heavy Fermi-liquid formation in the valence fluctuating $\alpha$-YbAlB${}_4$
• Kondo destruction and valence fluctuations in an Anderson model
• T/B Scaling in beta-YbAlB4
• Synchrotron X-ray Spectroscopy Study on the Valence State in alpha- and beta-YbAlB4 at Low Temperatures and High Magnetic Fields
• T/B scaling of magnetization in the mixed valent compound β-YbAlB4
• Low temperature magnetization of the quantum critical heavy fermion superconductor $\beta$-YbAlB${}_4$

Cited by in corpus (5)

• Kondo hybridization and quantum criticality in $\beta$-YbAlB${}_4$ by laser-ARPES
• Ubiquity of Unconventional Phenomena Associated with Critical Valence Fluctuations in Heavy Fermion Metals
• Topological basis for understanding the behavior of the heavy-fermion metal $\beta -\mathrm{YbAl}{\mathrm{B}}_4$ under application of magnetic field and pressure
• Observation of a Critical Charge Mode in a Strange Metal
• Intact Quasiparticles at an Unconventional Quantum Critical Point