A New Material Pathway for AI Data Centres and Quantum Networks

In a discovery that could have far-reaching implications for the future of computing, communications and sensing technologies, researchers in Bengaluru have demonstrated for the first time that the way a metal interacts with light can be actively controlled using mechanical strain . The breakthrough challenges a decades-old belief in physics that the optical properties of metals remain fixed once a material is fabricated and opens the door to a new generation of programmable photonic devices .

The research, carried out by scientists at the Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) , has been published in the prestigious journal Nano Letters . Beyond its scientific significance, the work is attracting attention because of its potential relevance to some of the world’s fastest-growing technology sectors, including artificial intelligence (AI) , quantum computing , advanced telecommunications, semiconductor manufacturing and next-generation sensing systems.

Understanding the World of Metal Optics

At the heart of the breakthrough lies a field known as plasmonics , often referred to as metal optics . Unlike conventional optics, which uses lenses, mirrors and optical fibres to manipulate light, plasmonics exploits the collective motion of free electrons in metals. When light strikes a metallic surface, these electrons oscillate together, creating what are known as plasmons. This phenomenon enables light to be confined and controlled at dimensions far smaller than its natural wavelength, overcoming a fundamental limitation of traditional optics.

Scientists have long viewed plasmonics as a key enabling technology for future applications ranging from ultra-sensitive biosensors and cancer diagnostics to high-speed communications, photonic circuits and advanced imaging systems. Yet one major challenge has persisted: the optical properties of plasmonic materials are typically fixed once they are manufactured.

The JNCASR team has now demonstrated a way to overcome that limitation.

Why Titanium Nitride Matters

The researchers focused on Titanium Nitride (TiN) , a material increasingly regarded as one of the most promising alternatives to gold and silver in plasmonic applications. While precious metals exhibit excellent optical performance, they are costly, less durable and difficult to integrate into modern semiconductor production.

TiN, by contrast, combines a gold-like plasmonic response with exceptional thermal stability, chemical resistance and full compatibility with CMOS semiconductor fabrication processes . It is already widely used in microprocessors, memory chips and semiconductor manufacturing as a protective coating and diffusion barrier.

This compatibility makes the discovery especially significant because it involves a material that the semiconductor industry already manufactures and understands at scale.

How the Experiment Was Conducted

To isolate the role of strain, the researchers fabricated two ultrathin TiN films, each measuring just 10 nanometres thick . One film was grown on a magnesium oxide (MgO) substrate without strain, while the other was deposited on an aluminium scandium nitride (Al₀.₃Sc₀.₇N) buffer layer that introduced controlled tensile strain into the material.

Using electron energy loss spectroscopy (EELS) within a scanning transmission electron microscope, Diksha Dadhich and colleagues from the research group led by Prof. Bivas Saha mapped plasmon resonance energy across the films at near-atomic resolution.

The strained TiN film exhibited a pronounced blue shift of 0.30–0.45 electron volts in plasmon resonance energy compared with the strain-free sample. The shift closely followed local variations in strain, providing compelling evidence that mechanical deformation was directly modifying the electronic and optical behaviour of the metal.

The Science Behind the Breakthrough

To uncover the mechanism responsible for this effect, the team performed density functional theory (DFT) calculations. The simulations revealed that tensile strain lowers the energy required to create nitrogen vacancies within the TiN crystal lattice.

These vacancies act as electron donors, increasing the concentration of free electrons inside the material. The higher electron density raises the plasma frequency , the fundamental parameter governing how metals interact with light, thereby producing the observed shift in plasmon resonance.

In simple terms, the process follows a clear chain:

Mechanical Strain → Nitrogen Vacancies → More Free Electrons → Higher Plasma Frequency → Tunable Optical Properties

Additional confirmation came from spectroscopic ellipsometry and high-resolution X-ray diffraction measurements, strengthening the conclusion that strain can act as a powerful new control mechanism for plasmonic materials.

Why This Matters for the Semiconductor Industry

While the scientific achievement is significant in its own right, its broader technological implications may prove even more important.

Modern semiconductor chips are facing a growing challenge known as the data movement bottleneck . As computing systems become more powerful, especially in AI applications, transferring information between processors, memory and storage consumes increasing amounts of energy and time.

To address this problem, the global technology industry is investing heavily in silicon photonics , a field that uses light instead of electrical signals to transmit data. Optical communication offers dramatically higher bandwidth and lower power consumption than conventional electronic interconnects.

Technology giants such as NVIDIA , Intel , AMD , IBM , and TSMC are investing billions of dollars in photonic technologies to support the next generation of computing infrastructure.

Because TiN is already CMOS-compatible, the JNCASR discovery offers a realistic pathway toward integrating tunable optical components into future semiconductor platforms.

The Missing Link for Generative AI?

The rise of Generative AI has dramatically increased demand for high-performance computing infrastructure. Training and running large AI models requires the movement of enormous volumes of data between processors, memory systems and networking equipment.

Industry experts increasingly believe that future AI systems will depend on photonic chips and optical interconnects to overcome the limitations of conventional electronics. Several leading technology companies are already developing optical communication technologies specifically for AI data centres.

The Bengaluru breakthrough is significant because it demonstrates that plasmonic materials can become programmable after fabrication . In the future, such tunable optical components could help create adaptive photonic hardware capable of dynamically responding to changing AI workloads, improving efficiency while reducing energy consumption.

Although the research is not itself an AI technology, it contributes to the foundational materials science that may underpin future generations of AI infrastructure.

A Potential Building Block for Quantum Computing

The findings also have important implications for quantum technologies .

Many emerging quantum computing architectures rely on photons as carriers of quantum information because light can travel long distances with minimal loss and is less susceptible to environmental disturbances than many other quantum systems.

Researchers around the world are developing quantum photonic integrated circuits , which combine optical and quantum components on semiconductor chips. One of the major challenges in this field is creating compact, scalable and reconfigurable optical elements.

The ability to dynamically tune plasmonic properties in a CMOS-compatible material such as TiN introduces a potentially valuable tool for future quantum photonic systems. While the JNCASR discovery is not a quantum computer, it provides a new materials platform that could contribute to the development of scalable quantum photonic hardware.

From Static Materials to Programmable Photonics

Perhaps the most significant aspect of the breakthrough is that it transforms plasmonics from a passive technology into an active and programmable platform .

Until now, plasmonic devices have generally possessed fixed optical properties determined during manufacturing. The JNCASR work suggests that future devices could alter their optical behaviour dynamically through mechanical control.

Such capabilities could lead to programmable photonic chips , optical AI accelerators , adaptive biosensors, reconfigurable optical circuits, smart metasurfaces, lab-on-chip diagnostic devices, quantum photonic processors and next-generation communication systems.

A Trillion-Dollar Opportunity

The economic significance is equally striking.

The global photonics market is estimated to exceed $1 trillion , serving industries ranging from telecommunications and healthcare to defence and consumer electronics. The market for plasmonic materials alone is projected to grow from approximately $13 billion today to more than $57 billion over the next decade , driven by expanding demand from AI, quantum computing and advanced communications.

India currently accounts for only a modest share of advanced photonics manufacturing but contributes significantly to global semiconductor design talent. With initiatives such as the India Semiconductor Mission accelerating investments in semiconductor fabrication and advanced materials, discoveries like this could help strengthen India's position in strategically important future technologies.

Researchers See a New Control Knob for Light

“Our work shows that strain is a powerful and previously underexplored control knob for plasmonic properties in metals. The ability to mechanically reconfigure the optical response of a CMOS-compatible material like TiN transforms plasmonics from a static platform to an active and programmable one, with exciting implications for on-chip photonics and optical sensing,” said Prof. Bivas Saha , Associate Professor at JNCASR and corresponding author of the study.

The research also involved collaboration with Dr. Magnus Garbrecht , Vijay Bhatia , and Ashalatha Indiradevi Kamalasanan Pillai from the University of Sydney .

India at the Forefront of an Emerging Technology

As the global race intensifies to develop faster, smarter and more energy-efficient technologies for the AI era, the Bengaluru discovery represents far more than an academic achievement.

By showing that the optical properties of a semiconductor-compatible metal can be dynamically controlled, the JNCASR team has introduced a new approach that could influence the future design of photonic chips, AI hardware and quantum technologies. In doing so, the researchers have positioned India at the forefront of a rapidly evolving field that many experts believe will play a central role in the next revolution in computing and communications.