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Published on: September 25, 2020
Macroscopic invisibility cloak for visible light
Baile Zhang1, Yuan Luo, Xiaogang Liu
1Singapore-MIT Alliance for Research and Technology Centre, Singapore 117543, Singapore.
Physical Review Letters
|March 17, 2011
Summary
Researchers created a practical invisibility cloak using transformation optics and calcite. This device can hide macroscopic objects in visible light, overcoming a major challenge in optical engineering.
Area of Science:
- Optics and Photonics
- Materials Science
Background:
- Invisibility cloaks are a long-standing concept in science fiction.
- Achieving true invisibility for macroscopic objects across the visible light spectrum remains a significant scientific challenge.
Purpose of the Study:
- To experimentally demonstrate a practical invisibility cloak for macroscopic objects.
- To overcome the limitations of previous invisibility cloak research by working in the visible light spectrum.
Main Methods:
- Incorporation of transformation optics principles into conventional optical lens fabrication.
- Utilization of low-cost materials and simple manufacturing techniques.
- Fabrication of a transparent cloak using two pieces of calcite.
Main Results:
- Successful cloaking of a macroscopic object up to 2 mm in height.
- Demonstration of cloaking across a bandwidth encompassing red, green, and blue light.
- Operation within a transparent liquid environment.
Conclusions:
- The study presents a viable method for creating invisibility cloaks using accessible materials and techniques.
- This research advances the practical realization of invisibility technology beyond theoretical concepts.
- The demonstrated cloak operates effectively across the visible light spectrum for macroscopic objects.
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