Thermodynamic Investigation of Metamagnetism in Pulsed High Magnetic Fields on Heavy Fermion Superconductor UTe${}_2$

Abstract

We investigated the thermodynamic property of the heavy fermion superconductor UTe${}_2$ in pulsed high magnetic fields. The superconducting transition in zero field was observed at $T_{\mathrm{c}}$=1.65 K as a sharp heat capacity jump. Magnetocaloric effect measurements in pulsed-magnetic fields obviously detected a thermodynamic anomaly accompanied by a first-order metamagnetic transition at $\mu$${}_0$$H_{\mathrm{m}}$=36.0 T when the fields are applied nearly along the hard-magnetization $b$-axis. From the results of heat capacity measurements in magnetic fields, we found a drastic diverging electronic heat capacity coefficient of the normal state $\gamma$${}_{\mathrm{N}}$ with approaching $H_{\mathrm{m}}$. Comparing with the previous works via the magnetic Clausius-Clapeyron relation, we unveil the thermodynamic details of the metamagnetic transition. The enhancement of the effective mass observed as the development of ${\gamma }_{\mathrm{N}}$ indicates that quantum fluctuation strongly evolves around $H_{\mathrm{m}}$; it assists the superconductivity emerging even in extremely high fields.

6 pages, 6 figures, accepted for publication in JPSJ

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Cited by in corpus (7)

• Multiple Superconducting Phases and Unusual Enhancement of the Upper Critical Field in UTe2
• Inhomogeneous Superconducting State Probed by ${}^{125}$Te NMR on UTe$_2
• Enhancement and Discontinuity of Effective Mass through the First-Order Metamagnetic Transition in UTe${}_2$
• Expansion of the high field-boosted superconductivity in UTe2 under pressure
• High-resolution Calorimetry in Pulsed Magnetic Fields
• Magnetovolume Effect on the First-Order Metamagnetic Transition in UTe${}_2$
• On Sharp Enhancement of Effective Mass of Quasiparticles and Coefficient of T^{2} Term of Resistivity around First-Order Metamagnetic Transition Observed in UTe_{2}