Ultrathin, Flexible Mantle Cloak for Camouflaging and Total Scattering Suppression

Physical Sciences : Electrical

Available for licensing


  • Andrea Alu, Ph.D. , Electrical and Computer Engineering
  • Jason Soric , Electrical and Computer Engineering
  • Pai-Yen Chen , Electrical and Computer Engineering
  • David Rainwater , Applied Research Laboratories
  • Aaron Kerkhoff , Applied Research Laboratories

Background/unmet need

Electromagnetic invisibility cloaks have become one of the most exciting new applications in metamaterial technology. In recent years, it has been theoretically shown and experimentally demonstrated that the anomalous wave interaction of artificial materials and metamaterials may be tailored to largely reduce the overall visibility of a given object in different frequency regions (spanning radiofrequencies (RF), infrared, and visible light).

Further, thanks to recent advances in micro/nanofabrication, passive and active approaches to metamaterial cloaking have been successfully developed, making way for a variety of fascinating applications that include not only camouflaging and low observability, but also noninvasive sensing and low-noise communications.

Theoretical foundations for transformation-based cloaks are particularly well understood, but there have been inherent limitations in the usefulness of applications that require an overall cloak thickness that is comparable to the size of the region to be cloaked. Researchers at from the Department of Electrical and Computer Engineering (ECE) at The University of Texas at Austin have discovered a novel approach towards these limitations.

Invention Description

The invention is a technique for patterning an ultrathin surface of less than 0.2mm with metal such that the specific forms, amplitudes, phase and shapes of the induced currents can strongly suppress microwave scattering from an arbitrary object, in all directions and for all forms of excitation, making it essentially undetectable. The inclusion of active circuitry in the metasurface allows large bandwidths of operation, broader than any of the currently available techniques based on passive metamaterials.

Though the invention has been tested mostly at microwave frequencies to date, its design properties are considered to be favorable across other frequencies as well, THz being an example. The inventors have multiple prototypes to demonstrate this concept.


    The invention effectively allows for the same cloaking effect that can be seen in comparable metamaterial technologies currently in the field, but over much larger bandwidths and with greatly reduced thickness.


  • Has been tested on a variety of geometries
  • Simple and inexpensive to fabricate
  • Highly resilient to loss and manufacturing imperfections
  • Allows for defeat of bistatic radar instruments

Market potential/applications

Military (camouflaging and reduction of radar/sonar detectability of hot spots); Noninvasive biomedical measurements; Medical biomarkers; Optical switches; Interference minimization (communication systems); Energy harvesting

Development Stage

Lab/bench prototype