Metamaterials are emerging as a transformative technology in the RF and microwave markets. Taken in the abstract, a metamaterial is a composite material that is used to affect electromagnetic waves. While practical models and methods, along with artificial metamaterials, are new developments within the past three decades or so, explorations of using artificial dielectrics to influence electromagnetic waves were reported at the end of the 19th century.1
Figure 1 Xerox PARC in Palo Alto. Source: en.wikipedia.org/w/index.php?title=File:Parcentrance.jpg
One of the biggest drivers of fundamental research into and implementation of metamaterials has been the Xerox Palo Alto Research Center (PARC). Metamaterial technology originating from this research at Xerox PARC has enabled breakthroughs in fields ranging from telecommunications and radar to security screening. This article discusses metamaterial fundamentals, along with the evolution of this technology at Xerox PARC from inception to commercialization. As is often the case with new technologies at research centers, the efforts have incubated several companies. The article also addresses companies like Kymeta, Echodyne, Pivotal Commware and Evolv Technology that have spun out of activities at Xerox PARC. Each company is harnessing metamaterials in unique and innovative ways to enable new and exciting possibilities in a broad range of industries and applications. These activities are also sparking tremendous interest in the future and potential of this technology. Figure 1 shows the entrance to the Xerox PARC facility in Palo Alto, Calif.
UNDERSTANDING METAMATERIALS
Metamaterials are typically composed of structured arrays of elements at sub-wavelength sizes. These elements interact with the electromagnetic waves. The structured design allows researchers and designers to control the wave propagation properties by manipulating how these materials interact with light, sound or even thermal energy. A notable property of metamaterials is their ability to achieve a negative refractive index, which causes light to bend in the opposite direction when passing through the material. This phenomenon can be applied to create what are called “superlenses.” This phenomenon in these lenses enables resolution beyond the diffraction limit, the smallest detail that a lens can resolve, of conventional lenses. By extending this limit, metamaterial lenses can have much better resolution than traditional lenses. In addition, the negative refractive index can be used for stealth technologies that could render objects effectively invisible by bending light around them.
Figure 2 Split-ring resonators. Source: en.wikipedia.org/wiki/Metamaterial
The properties of metamaterials are determined by their internal structure rather than their composition alone. These properties and the dependence on internal structure open many exciting avenues for customization. By altering the size, shape or arrangement of these internal elements, the metamaterial can be tailored to exhibit specific properties. This ability to customize can have far-reaching implications for telecommunications applications, where metamaterials can improve the performance of antennas, filters and waveguides by optimizing signal propagation and reducing interference. Figure 2 shows a negative-index metamaterial array of split-ring resonators realized in an array measuring 10 × 100 × 100 mm. In this example, the array consists of 3 × 20 × 20 unit cells.
METAMATERIAL FOUNDATIONS: THE XEROX PARC ERA
At Xerox PARC, the exploration of metamaterials focuses on three primary areas: telecommunications, optics and energy. For telecommunications applications, metamaterials are used to enhance signal transmission and reception. There are a variety of telecommunications applications for metamaterials, including reconfigurable intelligent surfaces (RIS), that can be used in antennas for beamforming, polarization control, signal redirection and signal strength enhancement. These developments will be significant in efforts to improve wireless network coverage and capacity, along with enabling the development of IoT. PARC researchers have shown that metamaterial structures enhance the efficiency and range of wireless communication systems, making them more resilient to interference and capable of operating at higher frequencies.
In optics, Xerox PARC’s metamaterials research aims to develop advanced lenses and imaging systems. Traditional lenses rely on the curvature and refractive index of glass or plastic to focus light. Metamaterial lenses use their structural properties to achieve similar effects but with greater control and the ability to manipulate the light waves. The expectation is that this research and these developments will lead to ultra-thin, lightweight lenses with applications in cameras, microscopes and even virtual and augmented reality devices that are important to the emerging 6G vision.
Xerox PARC’s exploration of metamaterials also extends to the energy sector, where these materials can be used to enhance the efficiency of photovoltaic cells, along with solar energy and energy storage solutions. Research is showing that the thermal or electromagnetic properties of metamaterials can be tailored to enable solar cells to capture a broader spectrum of sunlight or concentrate solar energy more effectively. Additionally, metamaterials can be designed to store thermal energy or to control heat transfer, which has applications in energy-efficient buildings and thermal management systems in electronics.
Xerox PARC has long been known for innovative research in computing and materials science. The company has played a pivotal role in metamaterial development. Since metamaterials are engineered composite materials, the Xerox PARC researchers are focusing on developing intricate structures that enable metamaterials to manipulate light, sound and radio waves beyond the limitations of natural materials. Key advancements from Xerox PARC include the development of metamaterial lenses, enabling compact and high-resolution imaging systems and other breakthroughs that continue to lay the groundwork for practical applications in telecommunications, sensing and other applications. In late April of 2023, Xerox announced the donation of the lab to SRI International, a non-profit research institute with the hopes of further building, expanding and scaling capabilities among a diverse set of technology and scientific areas.
XEROX PARC AS AN INCUBATOR
As mentioned, some of these developments have grown beyond Xerox PARC and spawned the formation of new companies. The rest of this article will look at some of the companies that have grown out of activities at Xerox PARC with some insight into the activities at these companies.
Kymeta Corporation: Metamaterials Revolutionizing Satellite Communications
Founded in 2012, Kymeta Corporation emerged from Xerox PARC’s metamaterial research with a mission to improve satellite communications. Kymeta’s core technology revolves around metamaterial-based electronically steerable antennas (ESAs). Traditional satellite antennas, such as parabolic dishes, are bulky and mechanically cumbersome, limiting their application in mobile and remote environments. Kymeta’s ESAs use metamaterials to electronically steer beams without moving parts, offering significant advantages in terms of size, weight and adaptability. These antennas enable high speed, mobile satellite connectivity, bridging the digital divide in remote areas and enhancing communication capabilities for maritime, aviation and military sectors.
Technical Capabilities of Kymeta’s Products:
- Metamaterial Antennas: Kymeta’s ESAs use metamaterials to steer beams across the satellite spectrum electronically. These antennas provide connectivity in mobile environments where deploying traditional antennas would present challenges.
- Compact Form Factor: By eliminating the need for mechanical components, Kymeta’s antennas are much smaller and lighter than conventional satellite dishes, making them well-suited for integration into vehicles, aircraft and portable communication systems
- Adaptability and Efficiency: Metamaterial-based design enables Kymeta’s antennas to adjust beam direction and shape dynamically. These features optimize signal strength and minimize interference to enhance communication efficiency.
Kymeta’s solutions are being widely adopted, establishing the company as a leader in metamaterial applications for satellite communications.
Echodyne Corporation: Metamaterials Redefining Radar Systems
Echodyne Corporation, founded in 2014, specializes in metamaterial-based radar systems that improve detection and imaging performance. Traditional radar systems rely on large, mechanically scanned arrays to achieve high-resolution and accuracy. Echodyne’s metamaterial ESAs are a compact, solid-state alternative that provides rapid beam steering and high-resolution imaging.
Technical Capabilities of Echodyne’s Products:
- Metamaterial ESAs: Echodyne’s radar systems leverage metamaterials to electronically steer beams with precision, enabling rapid scanning and better resolution than conventional radars
- Enhanced Imaging: The use of metamaterials allows Echodyne’s radars to achieve finer resolution and improved signal clarity, essential for applications such as autonomous vehicles, perimeter security and drone detection
- Compact and Lightweight: By eliminating bulky mechanical parts, Echodyne’s metamaterial-based radars are more portable and easier to integrate into various platforms without compromising performance.
Echodyne’s radar solutions have advanced situational awareness across industries, demonstrating the potential of metamaterial technologies.
Pivotal Commware: Metamaterials Enabling 5G Communications
Pivotal Commware, established in 2016, focuses on using metamaterials to enhance wireless communications, particularly for 5G networks. The transition to 5G introduces challenges such as signal propagation at higher mmWave frequencies and the need for precise beamforming. Beamforming is a technique that focuses a wireless signal toward a specific direction rather than broadcasting it in all directions. This technique reduces interference and allows signals to overcome obstacles more easily. Pivotal Commware’s antennas use metamaterials to implement holographic beamforming, dynamically shaping and steering radio waves for optimal coverage and performance.
Technical Capabilities of Pivotal Commware’s Products:
- Holographic Beamforming Antennas: Pivotal Commware’s antennas use metamaterials to implement holographic beamforming, dynamically shaping and steering radio waves for optimal coverage and performance
- mmWave Optimization: Metamaterial-based antennas improve the efficiency and range of mmWave transmissions, facilitating the deployment of 5G networks in urban environments and beyond
- Adaptive Beam Steering: By adjusting the beam direction in real-time, Pivotal Commware’s antennas mitigate signal blockage and interference, ensuring consistent and reliable connectivity for 5G applications.
Pivotal Commware’s metamaterial solutions are accelerating the deployment of 5G infrastructure worldwide, addressing challenges in next-generation wireless communications.
Evolv Technology: Metamaterials Enhancing Security Screening
Evolv Technology, founded in 2013, applies metamaterials to advance security screening systems, transforming how threats are detected and mitigated in public venues.
Technical Capabilities of Evolv Technology’s Products:
- Metamaterial Sensors: Evolv Technology’s security screening systems employ metamaterial sensors capable of detecting a wide range of threats, including metallic and non-metallic items, with high accuracy and minimal false alarms
- High Throughput Screening: The integration of metamaterial technology enables Evolv’s systems to process large volumes of individuals efficiently, enhancing throughput rates at security checkpoints
- Non-Intrusive Screening: Unlike traditional methods that require physical contact or removal of belongings, Evolv’s metamaterial-based sensors allow for discreet and non-intrusive screening, improving the overall passenger experience.
Evolv Technology’s innovative use of metamaterials is helping to redefine and improve security screening standards, offering scalable solutions that prioritize safety and efficiency in public spaces.
FUTURE DIRECTIONS AND IMPLICATIONS
The evolution of metamaterials from theoretical concepts to practical implementation starts with companies like Xerox PARC. It is evolving with companies that have spun out of Xerox PARC, like Kymeta, Echodyne, Pivotal Commware and Evolv Technology, to commercialize the technology. The number of companies working with metamaterials underscores the potential of the technology across many industries and applications. As research and development activities in metamaterials continue to evolve, more opportunities for metamaterial innovation and integration into new applications will emerge.
Metamaterials, born from research at Xerox PARC, are catalyzing a wave of innovation and spawning companies that will continue to lead the charge in satellite communications, radar systems, 5G technology and security screening. Each company, Kymeta, Echodyne, Pivotal Commware and Evolv Technology, highlights the promise of metamaterials in pushing technological boundaries and addressing complex challenges. As these companies continue to innovate and expand their applications, metamaterials are poised to shape the future trajectory of technology, unlocking new possibilities for connectivity, security and beyond.
Reference
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