Bridging the Gap - Rediscovering Black Phosphorus As an Anisotropic Layered Material for Electronics and Optoelectronics

In this talk, I will discuss our recent work in introducing black phosphorus (BP) to the layered-material family as a novel anisotropic 2D material for electronic and optoelectronic applications [1] [2]. Narrow gap BP thin film (0.3 eV in bulk) serendipitously fill the energy space between zero-gap graphene and large-gap TMDCs, making it an promising material for near and mid-infrared optoelectronics [3]. BP thin films show high mobility above 650 cm²/V.s at room temperature along the light effective mass (x) direction, implying its promising potential for high frequency, thin-film electronics. Furthermore, its anisotropic nature within the plane of the layers may allow for the realization of conceptually new electronic and photonic devices impossible in other 2D materials. In the talk, I will also present our work in demonstrating 20 GHz black phosphorus radio-frequency transistors [4]. Our recent progress in characterizing the optical properties of monolayer BP [5] and in achieving large-area synthesis of black phosphorus thin film will also be discussed. I will conclude with remarks on promising future directions of black phosphorus research and how this new material is expected to benefit the next-generation electronics and photonics technologies.

References

[1] X. Ling, H. Wang*, S. Huang, F. Xia, M. Dresselhaus* “The Renaissance of Black Phosphorus” Proceedings of the National Academy of Sciences (PNAS), 112, 15, 4523-4530, 2015. doi: 10.1073/pnas.1416581112.

[2] F. Xia*, H. Wang*, Y. Jia “Rediscovering Black Phosphorus as an Anisotropic Layered Material for Optoelectronics and Electronics” Nature Communications, 5:4458 doi: 10.1038/ncomms5458, 2014.

[4] F. Xia, H. Wang, D. Xiao, M. Dubey, A. Ramasubramaniam “Two-Dimensional Material Nanophotonics” Nature Photonics, 8 (12), 899-907.

[3] H. Wang*, X. Wang, F. Xia*, L, Wang, H. Jiang, Q. Xia, M. Chin, M. Dubey, S.-J. Han “Black Phosphorus Radio Frequency Transistors” Nano Lett., 14 (11), 6424-6429, 2014.

[5] X. Wang, A. M. Jones, K. L. Seyler, V. Tran, Y. Jia, H. Zhao, H. Wang, L. Yang, X. Xu, F. Xia "Highly Anisotropic and Robust Excitons in Monolayer Black Phosphorus" Nature Nanotechnology, published on line,  2015. doi:10.1038/nnano.2015.71.