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Title: TiN‐Au/HfO 2 ‐Au Multilayer Thin Films with Tunable Hyperbolic Optical Response
Abstract Hyperbolic metamaterials (HMM) possess significant anisotropic physical properties and tunability and thus find many applications in integrated photonic devices. HMMs consisting of metal and dielectric phases in either multilayer or vertically aligned nanocomposites (VAN) form are demonstrated with different hyperbolic properties. Herein, self‐assembled HfO2‐Au/TiN‐Au multilayer thin films, combining both the multilayer and VAN designs, are demonstrated. Specifically, Au nanopillars embedded in HfO2and TiN layers forming the alternative layers of HfO2‐Au VAN and TiN‐Au VAN. The HfO2and TiN layer thickness is carefully controlled by varying laser pulses during pulsed laser deposition (PLD). Interestingly, tunable anisotropic physical properties can be achieved by adjusting the bi‐layer thickness and the number of the bi‐layers. Type II optical hyperbolic dispersion can be obtained from high layer thickness structure (e.g., 20 nm), while it can be transformed into Type I optical hyperbolic dispersion by reducing the thickness to a proper value (e.g., 4 nm). This new nanoscale hybrid metamaterial structure with the three‐phase VAN design shows great potential for tailorable optical components in future integrated devices.  more » « less
Award ID(s):
2016453
PAR ID:
10528426
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Small Methods
Edition / Version:
1
ISSN:
2366-9608
Format(s):
Medium: X Size: 2MB Other: PDF-A
Size(s):
2MB
Sponsoring Org:
National Science Foundation
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