Surface Transport and Quantum Hall Effect in Ambipolar Black Phosphorus Double Quantum Wells

Son Tran; Jiawei Yang; Nathaniel Gillgren; Timothy Espiritu; Yanmeng Shi; Kenji Watanabe; Takashi Taniguchi; Seongphill Moon; Hongwoo Baek; Dmitry Smirnov; Marc Bockrath; Ruoyu Chen; Chun Ning Lau

arXiv · 1703.04911

Surface Transport and Quantum Hall Effect in Ambipolar Black Phosphorus Double Quantum Wells

Son Tran·Jiawei Yang·Nathaniel Gillgren·Timothy Espiritu·Yanmeng Shi·Kenji Watanabe·Takashi Taniguchi·Seongphill Moon·Hongwoo Baek·Dmitry Smirnov·Marc Bockrath·Ruoyu Chen·Chun Ning Lau

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Abstract

Quantum wells constitute one of the most important classes of devices in the study of 2D systems. In a double layer QW, the additional "which-layer" degree of freedom gives rise to celebrated phenomena such as Coulomb drag, Hall drag and exciton condensation. Here we demonstrate facile formation of wide QWs in few-layer black phosphorus devices that host double layers of charge carriers. In contrast to tradition QWs, each 2D layer is ambipolar, and can be tuned into n-doped, p-doped or intrinsic regimes. Fully spin-polarized quantum Hall states are observed on each layer, with enhanced Lande g-factor that is attributed to exchange interactions. Our work opens the door for using 2D semiconductors as ambipolar single, double or wide QWs with unusual properties such as high anisotropy.

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Son Tran, Jiawei Yang, Nathaniel Gillgren, Timothy Espiritu, Yanmeng Shi, Kenji Watanabe, Takashi Taniguchi, Seongphill Moon, Hongwoo Baek, Dmitry Smirnov, Marc Bockrath, Ruoyu Chen, Chun Ning Lau. 2017-03-15. Surface Transport and Quantum Hall Effect in Ambipolar Black Phosphorus Double Quantum Wells. https://arxiv.org/abs/1703.04911

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