A Reconfigurable Color Reflector by Selective Phase Change of GeTe in a Multilayer Structure

Abstract

It is shown that a phase change material (PCM), germanium telluride (GeTe), when integrated into a subwavelength layered optical cavity, can produce widely tunable reflective colors. It is shown that the crystallization temperature (Tx) of GeTe is dependent on the film thickness for thin films of less than ≈20 nm, which is exploited for color tuning. Four colors from the same physical structure are demonstrated by electrical heating, through novel optical and thermal engineering of a thin film stack that includes two GeTe layers with only a single integrated joule heater element. The selective sensitivity to incident light angle and low polarization dependence, as well as the low static power consumption of this device make it a good candidate for potential consumer electronics applications.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jan 02, 2019
Source ID
10.1002/adom.201801214

Entities

People

  • L. Jay Guo
  • Mina Rais‐Zadeh
  • Mohsen Jafari

Organizations

  • California Institute of Technology
  • Defense Advanced Research Projects Agency
  • University of Michigan

Tags

Fields of Study

  • Physics

Readers

  • Nanofabrication and Microfabrication.
  • Optical Physics and Photonics.
  • Solar Photovoltaics and Thermoelectric Devices.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene