Hyperbolic Dispersion Arising from Anisotropic Excitons in Two-Dimensional Perovskites

Peijun Guo, Wei Huang, Constantinos C. Stoumpos, Lingling Mao, Jue Gong, Li Zeng, Benjamin T. Diroll, Yi Xia, Xuedan Ma, David J. Gosztola, Tao Xu, John B. Ketterson, Michael J. Bedzyk, Antonio Facchetti, Tobin J. Marks, Mercouri G. Kanatzidis, and Richard D. Schaller
Phys. Rev. Lett. 121, 127401 – Published 19 September 2018
PDFHTMLExport Citation

Abstract

Excitations of free electrons and optical phonons are known to permit access to the negative real part of relative permittivities (ϵ<0) that yield strong light-matter interactions. However, negative ϵ arising from excitons has been much less explored. Via development of a dielectric-coating based technique described herein, we report fundamental optical properties of two-dimensional hybrid perovskites (2DHPs), composed of alternating layers of inorganic and organic sublattices. Low members of 2DHPs (N=1 and N=2) exhibit negative ϵ stemming from the large exciton binding energy and sizable oscillator strength. Furthermore, hyperbolic dispersion (i.e., ϵ changes sign with directions) occurs in the visible range, which has been previously achieved only with artificial metamaterials. Such naturally occurring, exotic dispersion stems from the extremely anisotropic excitonic behaviors of 2DHPs, and can intrinsically support a large photonic density of states. We suggest that several other van der Waals solids may exhibit similar behaviors arising from excitonic response.

  • Figure
  • Figure
  • Figure
  • Figure
  • Received 13 March 2018

DOI:https://doi.org/10.1103/PhysRevLett.121.127401

© 2018 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied PhysicsAtomic, Molecular & Optical

Authors & Affiliations

Peijun Guo1, Wei Huang2,3, Constantinos C. Stoumpos2, Lingling Mao2, Jue Gong4, Li Zeng5, Benjamin T. Diroll1, Yi Xia1, Xuedan Ma1, David J. Gosztola1, Tao Xu4, John B. Ketterson6, Michael J. Bedzyk5,6,7, Antonio Facchetti2,8, Tobin J. Marks2,3, Mercouri G. Kanatzidis2, and Richard D. Schaller1,2,*

  • 1Center for Nanoscale Materials, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, USA
  • 2Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA
  • 3Materials Research Center, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA
  • 4Department of Chemistry & Biochemistry, Northern Illinois University, DeKalb, Illinois 60115, USA
  • 5Applied Physics Program, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA
  • 6Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA
  • 7Department of Materials Science and Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA
  • 8Flexterra Corporation, 8025 Lamon Avenue, Skokie, Illinois 60077, USA

  • *schaller@anl.gov schaller@northwestern.edu

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 121, Iss. 12 — 21 September 2018

Reuse & Permissions
Access Options
CHORUS

Article Available via CHORUS

Download Accepted Manuscript
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Letters

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×