Dielectric and transient electrical response of SmB6 single crystals

We report results from an in–plane and out–of–plane impedance study on SmB6 single crystals, performed at low temperatures and over a wide frequency range. A universal equivalent circuit describes the dielectric behavior of this system across the transition, from surface to bulk dominated electrical...

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Bibliographic Details
Authors: Stankiewicz, Jolanta, Schlottmann, Pedro, Blasco, Javier, Ciomaga Hatnean, Monica, Balakrishnan, Geetha
Format: article
Status:Published version
Publication Date:2023
Country:España
Institution:Consejo Superior de Investigaciones Científicas (CSIC)
Repository:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/329782
Online Access:http://hdl.handle.net/10261/329782
Access Level:Open access
Keyword:Samarium hexaboride
Impedance spectroscopy
Current–controlled voltage oscillations
Description
Summary:We report results from an in–plane and out–of–plane impedance study on SmB6 single crystals, performed at low temperatures and over a wide frequency range. A universal equivalent circuit describes the dielectric behavior of this system across the transition, from surface to bulk dominated electrical conduction between 2 and 10 K. We identify the resistive, capacitive, and inductive contributions to the impedance. The equivalent inductance, obtained from fits to experimental data, drops drastically with increasing temperature, as the bulk starts to control electrical conduction. Self–sustained voltage oscillations, observed below 6 K across small crystals when biased with a dc current, point to a large SmB6 self–capacitance, likely brought by the surface states.