Sub-tesla on-chip nanomagnetic metamaterial platform for angle-resolved photoemission spectroscopy

Wenxin Li; Wisha Wanichwecharungruang; Mingyang Guo; Ioan-Augustin Chioar; Nileena Nandakumaran; Justin Ramberger; Senlei Li; Zhibo Kang; Jinming Yang; Donghui Lu; Makoto Hashimoto; Chunhui Rita Du; Chris Leighton; Peter Schiffer; Qiong Ma; Ming Yi; Yu He

doi:10.1021/acs.jpclett.5c03075

arXiv · 2509.15092

Sub-tesla on-chip nanomagnetic metamaterial platform for angle-resolved photoemission spectroscopy

Wenxin Li·Wisha Wanichwecharungruang·Mingyang Guo·Ioan-Augustin Chioar·Nileena Nandakumaran·Justin Ramberger·Senlei Li·Zhibo Kang·Jinming Yang·Donghui Lu·Makoto Hashimoto·Chunhui Rita Du·Chris Leighton·Peter Schiffer·Qiong Ma·Ming Yi·Yu He

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Abstract

Magnetically controlled states in quantum materials are central to their unique electronic and magnetic properties. However, direct momentum-resolved visualization of these states via angle-resolved photoemission spectroscopy (ARPES) has been hindered by the disruptive effect of magnetic fields on photoelectron trajectories. Here, we introduce an \textit{in-situ} method that is, in principle, capable of applying magnetic fields up to 1 T. This method uses substrates composed of nanomagnetic metamaterial arrays with alternating polarity. Such substrates can generate strong, homogeneous, and spatially confined fields applicable to samples with thicknesses up to the micron scale, enabling ARPES measurements under magnetic fields with minimal photoelectron trajectory distortion. We demonstrate this minimal distortion with ARPES data taken on monolayer graphene. Our method paves the way for probing magnetic field-dependent electronic structures and studying field-tunable quantum phases with state-of-the-art energy-momentum resolutions.

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Wenxin Li, Wisha Wanichwecharungruang, Mingyang Guo, Ioan-Augustin Chioar, Nileena Nandakumaran, Justin Ramberger, Senlei Li, Zhibo Kang, Jinming Yang, Donghui Lu, Makoto Hashimoto, Chunhui Rita Du, Chris Leighton, Peter Schiffer, Qiong Ma, Ming Yi, Yu He. 2025-09-18. Sub-tesla on-chip nanomagnetic metamaterial platform for angle-resolved photoemission spectroscopy. https://doi.org/10.1021/acs.jpclett.5c03075

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