Nonlinear near-field microwave probing of Andreev bound states in ultrathin YBa2Cu3O7−x films

IF 2.1 4区物理与天体物理 Q3 PHYSICS, CONDENSED MATTER

Solid State Communications Pub Date : 2025-03-02 DOI:10.1016/j.ssc.2025.115887

E.E. Pestov , E.A. Arkhipova , A.I. El’kina , D.V. Masterov , A.E. Parafin , S.A. Pavlov , P.A. Yunin , D.A. Savinov

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引用次数: 0

Abstract

Boundary surfaces in epitaxial films of high-temperature oxides can host Andreev bound states. At low temperatures, these states should contribute to nonlinear microwave response and strongly enhance it. Using the nonlinear near-field microwave technique, the temperature dependence of the third harmonic power

P_{3 ω} (T)

and its anisotropy in the

(a b)

plane have been studied for ultrathin

{YBa}_{2} {Cu}_{3} O_{7 - x}

films. We observe a kink on the dependence

P_{3 ω} (T)

at temperature

T_{kink} \sim 20 - 30 K

. For

T < T_{kink}

, the third harmonic power monotonously increases as the temperature decreases. Additionally, the nonlinear microwave response demonstrates a larger contribution when the supercurrent flows along the

a

and

b

axes of the films. Our experimental results indicate that these low temperature features can be associated with the presence of Andreev bound states at the twin boundaries and/or the film edges.

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来源期刊

Solid State Communications 物理-物理：凝聚态物理

CiteScore

3.40

自引率

4.80%

发文量

287

审稿时长

51 days

期刊介绍： Solid State Communications is an international medium for the publication of short communications and original research articles on significant developments in condensed matter science, giving scientists immediate access to important, recently completed work. The journal publishes original experimental and theoretical research on the physical and chemical properties of solids and other condensed systems and also on their preparation. The submission of manuscripts reporting research on the basic physics of materials science and devices, as well as of state-of-the-art microstructures and nanostructures, is encouraged. A coherent quantitative treatment emphasizing new physics is expected rather than a simple accumulation of experimental data. Consistent with these aims, the short communications should be kept concise and short, usually not longer than six printed pages. The number of figures and tables should also be kept to a minimum. Solid State Communications now also welcomes original research articles without length restrictions. The Fast-Track section of Solid State Communications is the venue for very rapid publication of short communications on significant developments in condensed matter science. The goal is to offer the broad condensed matter community quick and immediate access to publish recently completed papers in research areas that are rapidly evolving and in which there are developments with great potential impact.