Experimental realization of Majorana hinge and corner modes in intrinsic organic topological superconductor without magnetic field at room temperature

Kyoung Hwan Choi; Dong Hack Suh

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arXiv · 2101.05978

Experimental realization of Majorana hinge and corner modes in intrinsic organic topological superconductor without magnetic field at room temperature

Kyoung Hwan Choi·Dong Hack Suh

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Abstract

Exotic states of topological materials are challenging or impossible to create under ambient conditions.1-4 Moreover, it is unclear whether topological superconductivity, as a critical element for topological quantum computing, exists in any naturally occurring materials.5-7 Although these problems can be overcome through the combination of materials in heterostructures, there are still many requisites, such as low temperatures and specific magnetic fields.8,9 Herein, an intrinsic topological superconductor that does not depend on particular external conditions is demonstrated. It is accomplished utilizing the unique properties of polyaromatic hydrocarbons (PAHs), which have been proposed to have persistent ring current.10-12 According to the Su-Schrieffer-Heeger(SSH)13 and Kitaev14 models, PAHs can have a non-trivial edge mode, so that perpendicularly stacked PAHs are expected to have Majorana hinge and corner modes.15 Intrinsic persistent ring current of HYLION-12 is demonstrated by MPMS.16 Coherent Quantum Phase Slip(CQPS), the Constant Conductance Plateau (CCP) and the zero bias conductance peak(ZBP) which is signatures of hinge modes are confirmed through the Josephson junction device of pelletized orthorhombic phase organic crystals of HYLION-12 by transport spectroscopy.17,18 They are signatures of Majorana hinge and corner modes. In addition, the braidinglike operation by transport spectroscopy shows the emergence of the most important and critical elements of quantum computers that can be realized without an external magnetic field at room temperature.

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Kyoung Hwan Choi, Dong Hack Suh. 2021-01-15. Experimental realization of Majorana hinge and corner modes in intrinsic organic topological superconductor without magnetic field at room temperature. https://arxiv.org/abs/2101.05978

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