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Hybrid metal/semiconductor quantum dots for analog quantum simulation of non-Fermi liquid physics

ORAL

Abstract

Few-site semiconductor quantum dot arrays have provided controllable realizations of effective Hamiltonians. However, intersite inhomogeneity presents a major roadblock to scaling and tuning larger arrays. In contrast, the quasi-continuous level spectrum of hybrid metal-semiconductor quantum dots enables the design of arrays of such sites that behave essentially identically while retaining tunability of intersite coupling, providing a platform for simulating strong interactions. Recent work on a pair of hybrid metal/GaAs dots investigated a novel non-Fermi liquid critical point based on Kondo interactions mediated by the charge of the metallic island[1]. The islands had to be a few microns wide, given how ohmic contacts are made to GaAs. The surface Fermi level pinning in InAs provides a pathway for designing submicron hybrid dots with larger charging energy, enabling investigations of critical scaling over a broader temperature range. We have demonstrated the essential ingredients in an InAs quantum well – clean quantum point contacts[2], highly transparent transmission (>99%) of 1D modes into submicron metal islands, and hybrid metal/InAs dots – for building sizable arrays to gain insights into the Kondo lattice coherence in heavy-fermion materials.

1. Pouse, W. et al. arXiv:2108.12691 (2021)

2. Hsueh, C.L., Sriram, P. et al. Phys. Rev. B 105, 195303 (2022)

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Publication: Hsueh, C.L., Sriram, P. et al., Clean quantum point contacts in an InAs quantum well grown on a lattice-mismatched InP substrate, Phys. Rev. B 105, 195303 (2022).

Presenters

  • Praveen Sriram

    Stanford University

Authors

  • Praveen Sriram

    Stanford University

  • Connie L Hsueh

    Stanford University

  • Tiantian Wang

    Purdue University

  • Candice Thomas

    Purdue University, Department of Physics and Astronomy, Purdue University, Department of Physics and Astronomy, Purdue University,, Department of Physics and Astronomy and Birck Nanotechnology Center, Purdue University

  • Geoff C Gardner

    Purdue University, Materials Engineering, Purdue University, Department of Physics and Astronomy, Birck Nanotechnology Center, Purdue University

  • Marc A Kastner

    Stanford Univ

  • Michael J Manfra

    Purdue University, Microsoft Quantum Purdue, Purdue University, Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA; Microsoft Quantum Lab, Purdue University, West Lafayette, IN, USA, Physics and Astronomy, Purdue University, Department of Physics and Astronomy, Birck Nanotechnology Center, School of Electrical and Computer Engineering and Microsoft Quantum Lab West Lafayette, Purdue University, Department of Physics and Astronomy and Nanotechnology Center Purdue University, Microsoft Quantum Lab West Lafayette, Department of Physics and Astronomy, Birck Nanotechnology Center, School of Materials Engineering and School of Electrical and Computer Engineering, Purdue University

  • David Goldhaber-Gordon

    Stanford Univ, Stanford University