title: The renaissance of black phosphorus.
abstract: One hundred years after its first successful synthesis in the bulk form in 1914, black phosphorus (black P) was recently rediscovered from the perspective of a 2D layered material, attracting tremendous interest from condensed matter physicists, chemists, semiconductor device engineers, and material scientists. Similar to graphite and transition metal dichalcogenides (TMDs), black P has a layered structure but with a unique puckered single-layer geometry. Because the direct electronic band gap of thin film black P can be varied from 0.3 eV to around 2 eV, depending on its film thickness, and because of its high carrier mobility and anisotropic in-plane properties, black P is promising for novel applications in nanoelectronics and nanophotonics different from graphene and TMDs. Black P as a nanomaterial has already attracted much attention from researchers within the past year. Here, we offer our opinions on this emerging material with the goal of motivating and inspiring fellow researchers in the 2D materials community and the broad readership of PNAS to discuss and contribute to this exciting new field. We also give our perspectives on future 2D and thin film black P research directions, aiming to assist researchers coming from a variety of disciplines who are desirous of working in this exciting research field.
authors.affiliation: Department of Electrical Engineering and Computer Science and.
authors.forename: Xi
authors.initials: X
authors.lastname: Ling
authors.affiliation: Ming Hsieh Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089; and millie@mgm.mit.edu han.wang.4@usc.edu.
authors.forename: Han
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Electrical Engineering and Computer Science and.
authors.forename: Shengxi
authors.initials: S
authors.lastname: Huang
authors.affiliation: Department of Electrical Engineering, Yale University, New Haven, CT 06511.
authors.forename: Fengnian
authors.initials: F
authors.lastname: Xia
authors.affiliation: Department of Electrical Engineering and Computer Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139; millie@mgm.mit.edu han.wang.4@usc.edu.
authors.forename: Mildred S
authors.initials: MS
authors.lastname: Dresselhaus
keywords: 2D material; anisotropic; black phosphorus; nanoelectronic; optoelectronic
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