India Builds Multi-Architecture Quantum Computing Ecosystem at IISc

India is pursuing an unusually broad strategy in its attempt to build indigenous quantum computers, developing five different hardware architectures in parallel rather than committing the country’s National Quantum Mission to a single technological pathway.

At the centre of this effort is the Foundation for QC Innovation at the Indian Institute of Science, Bengaluru, the national Quantum Computing Thematic Hub established under the Government of India’s National Quantum Mission. The hub coordinates research spanning superconducting qubits, semiconductor spin qubits, photonic quantum processors, neutral-atom systems and trapped-ion quantum computers, while simultaneously developing fabrication facilities, control electronics, algorithms, cloud access and a domestic quantum startup ecosystem.

This diversified approach is significant because quantum computing has not yet produced a universally dominant hardware architecture. Different technologies offer different advantages in fidelity, scalability, operating temperature, connectivity and manufacturing. India is therefore attempting to develop expertise across several competing technological paths while the global industry is still determining which architectures will ultimately prove most practical.

IISc Leads India’s National Quantum Computing Hub

The Foundation for QC Innovation, or FQCI, has been incorporated as a Section 8 not-for-profit company by IISc Bengaluru under the National Quantum Mission implemented by the Department of Science and Technology.

FQCI says the hub currently connects 21 institutions and 52 researchers, with about ₹653 crore in committed funding for quantum-computing activities. Its mandate extends beyond basic research to the development of scalable indigenous quantum processors, fabrication infrastructure, control electronics, cloud-accessible quantum computers, skills and commercial technologies.

The larger National Quantum Mission has an allocation of ₹6,003.65 crore for 2023–2031 and operates through four major thematic hubs. IISc leads quantum computing, IIT Madras with C-DOT leads quantum communication, IIT Bombay leads quantum sensing and metrology, and IIT Delhi leads quantum materials and devices.

Together, the four hubs connect researchers and institutions across India, creating a national rather than institution-specific programme for developing quantum technologies.

Why India Is Not Betting Everything on One Quantum Computer

A conventional computer represents information using bits that take values of either zero or one. A quantum computer uses quantum bits, or qubits, whose physical implementation can take many different forms.

A qubit can be encoded in the electrical behaviour of a superconducting circuit, the spin of an electron inside silicon, the quantum state of an isolated ion, an individual neutral atom or even properties of a photon.

No architecture has yet conclusively established itself as the equivalent of silicon CMOS technology in conventional computing.

Superconducting systems can perform extremely fast operations but require sophisticated cryogenic infrastructure. Trapped ions can achieve exceptionally precise operations but present engineering challenges when expanded to very large systems. Neutral atoms can form large arrays, while semiconductor approaches could potentially exploit techniques developed by the existing chip industry. Photonic machines offer the possibility of operating without the extreme refrigeration demanded by some other approaches.

India’s decision to develop all of these technologies therefore acts as a form of technological risk diversification.

Rather than discovering several years from now that the architecture on which it concentrated has encountered a fundamental scaling problem, the country is building expertise across the principal approaches simultaneously.

Superconducting Qubits: Building Towards 100 Qubits

One major programme under the IISc-led hub is the development of superconducting quantum computers.

Superconducting qubits are microscopic electrical circuits fabricated using superconducting materials and operated at temperatures extremely close to absolute zero. At these temperatures, carefully designed circuits can behave according to quantum mechanical principles and function as artificial atoms.

This architecture has attracted major international investment because superconducting qubits can perform gates rapidly and can be manufactured using processes with some similarities to semiconductor fabrication.

India’s programme includes objectives to develop 24-qubit and 100-qubit superconducting quantum computers, alongside indigenous control electronics and cryogenic wiring systems capable of supporting machines with 100 qubits and beyond.

Developing the quantum processor alone is insufficient. The system also requires microwave-control electronics, specialised cabling, cryogenic equipment, amplifiers, packaging and sophisticated calibration software.

Indigenising these surrounding technologies is consequently just as important as producing the qubits themselves.

Semiconductor Qubits Could Leverage India’s Growing Chip Ecosystem

A second technological pathway involves semiconducting qubits, particularly electron spins inside silicon.

Quantum information can be stored in properties such as the spin of an individual electron confined within carefully fabricated semiconductor structures. Because the underlying devices are based on semiconductor materials, this architecture carries the long-term possibility of benefiting from decades of experience accumulated by the conventional semiconductor industry.

The FQCI programme includes a project for a 50-qubit quantum information processor using electron spins in silicon, alongside a separate effort aimed at demonstrating a highly scalable semiconductor-based quantum computer.

This approach could become particularly important for India as the country simultaneously expands semiconductor fabrication, chip design, compound-semiconductor research and advanced packaging capabilities.

However, manufacturing semiconductor quantum devices demands precision considerably beyond most conventional electronics. At the scale of individual electrons, microscopic defects, material impurities and electrical noise can disrupt quantum information.

The programme therefore requires advances not just in quantum physics but also in materials, nanofabrication and extremely sensitive control electronics.

Photonic Quantum Computing Uses Light Instead of Matter

India is also pursuing photonic quantum processors, where quantum information is encoded in individual particles of light.

Photons offer several attractive properties. They can travel long distances with relatively little interaction with their surroundings, they are naturally suited to optical networking and some photonic quantum systems can function without the extreme cryogenic refrigeration required by superconducting processors.

The IISc-led hub has established dedicated technical programmes for photonic quantum processor development and programmable photonic quantum computing using different degrees of freedom of individual photons.

IISc researchers have already demonstrated indigenous photonic quantum-computing capabilities, while the wider programme aims to progress towards increasingly scalable processors.

Photonic technology is particularly interesting because the boundary between quantum computing and quantum communication could eventually become less distinct. Quantum information encoded in photons is naturally compatible with optical transmission, potentially enabling distributed quantum processors or future quantum networks.

The engineering difficulty lies in reliably generating, manipulating, detecting and synchronising individual photons while keeping optical losses extremely low.

Neutral Atoms Offer a Route to Hundreds of Qubits

Another Indian programme is attempting something considerably larger in raw qubit numbers: a 400-plus-qubit neutral-atom quantum computer.

Neutral-atom quantum computing uses individual atoms trapped and arranged using precisely controlled laser fields. Arrays containing hundreds of atoms can be organised into programmable geometries, creating potentially large quantum systems.

The FQCI programme specifically targets a 400-plus-qubit system based on neutral rubidium atoms, supporting logical operations as well as analogue quantum computation.

The programme is led by researchers from the Raman Research Institute with participation from institutions including IISER Pune, IIT Roorkee, NISER Bhubaneswar, IIT Guwahati, IIT Kanpur and IIT Patna.

Neutral atoms have emerged internationally as an important contender because large arrays can be assembled relatively naturally compared with architectures in which every additional qubit requires complex wiring.

However, having hundreds of physical qubits is not equivalent to possessing a fault-tolerant quantum computer. Gate fidelity, error rates, connectivity, readout accuracy and the ability to perform useful algorithms remain equally important.

This distinction will remain crucial when comparing quantum machines based solely on headline qubit numbers.

India Also Targets a 50-Qubit Trapped-Ion Computer

The same technical group is developing a 50-qubit trapped-ion quantum computer based on calcium ions.

In this architecture, electrically charged atoms are held almost motionless using electromagnetic fields. Their internal quantum states can then serve as exceptionally stable qubits, while lasers are used for manipulation and readout.

Trapped ions are attractive because individual ions are fundamentally identical quantum objects. Unlike manufactured solid-state qubits, one calcium ion does not suffer from fabrication variations relative to another calcium ion.

The technology has consequently demonstrated some of the highest quantum gate fidelities achieved experimentally.

The challenge lies in scaling. Controlling large numbers of ions requires increasingly complex electromagnetic traps, laser systems and control architectures.

India’s programme therefore also envisages a hybrid system integrating atom-based analogue computing with ion-based digital quantum computing, exploring whether different quantum architectures could eventually complement one another rather than operate independently.

Five Architectures, But One Shared Technology Base

Although the five approaches use radically different physical qubits, much of the infrastructure surrounding them overlaps.

Quantum computers need highly precise electronics, photonics, nanofabrication, specialised materials, cryogenic equipment, packaging, testing systems, control software and algorithms.

India is therefore establishing shared national facilities rather than forcing every research group or startup to build expensive infrastructure independently.

Under the National Quantum Mission, four advanced quantum fabrication and central facilities worth approximately ₹720 crore are being established across IISc Bengaluru, IIT Bombay, IIT Kanpur and IIT Delhi.

For quantum computing specifically, IISc and IIT Bombay are expected to host central facilities for the fabrication of superconducting, photonic and spin-qubit processors, involving investment of around ₹557 crore.

The FQCI roadmap says India’s first-generation 100-qubit quantum processing unit is targeted for fabrication through these facilities by 2030.

Such infrastructure could become one of the most important long-term outcomes of the Mission.

Quantum devices often require fabrication equipment too expensive for an individual research laboratory or startup. National facilities capable of producing, packaging and characterising devices would allow Indian researchers to move prototypes from theoretical designs into physical hardware without depending entirely on overseas fabrication.

Quantum Computing Is More Than the Qubit

One of the strengths of the IISc strategy is its recognition that building a quantum computer involves much more than demonstrating qubits.

A functional machine requires a complete stack extending from materials and fabrication at the bottom to algorithms and applications at the top.

Superconducting systems require cryogenic electronics and microwave-control hardware. Semiconductor qubits require extremely precise nanofabrication and sensitive charge-detection systems. Photonic processors require single-photon sources, detectors and integrated optical circuits. Atomic systems need precision lasers, vacuum systems and advanced optical control.

All architectures need software capable of translating algorithms into physical operations while correcting or mitigating errors.

FQCI consequently includes quantum algorithms as one of its major technical areas and intends to provide secure cloud access to Indian quantum systems so researchers and companies can experiment without physically owning quantum hardware.

Cloud access is particularly important during the early decades of quantum computing because individual machines remain expensive and difficult to operate.

Startups Are Being Built Into the Programme

India is also attempting to prevent the National Quantum Mission from becoming exclusively an academic research programme.

FQCI has created the QC LEAP startup support programme, which invites Indian companies developing quantum-computing technologies to seek support from the hub.

Importantly, support is not restricted to companies attempting to manufacture entire quantum computers.

Startups developing driver electronics, specialised cables, quantum hardware subassemblies, control components and quantum algorithms can also participate.

This approach recognises that a future quantum industry could resemble the semiconductor or aerospace industries, where hundreds of specialised suppliers contribute individual technologies to a much larger system.

India may consequently build commercially successful quantum companies even before large fault-tolerant computers become commonplace.

Developing Indigenous Intellectual Property

The strategic importance of the programme extends beyond whether India produces the world’s first practical quantum computer.

Quantum technology is likely to become increasingly important to scientific simulation, materials development, optimisation, pharmaceutical research, cryptography and national security.

Countries that depend entirely on foreign quantum hardware could ultimately find themselves dependent upon overseas processors, cloud infrastructure and intellectual property in another foundational computing technology.

The National Quantum Mission is therefore attempting to establish Indian capability while the technology is still immature enough for new entrants to compete.

This is very different from entering an already mature industry decades after global technology standards and supply chains have been established.

The ₹6,003-Crore National Quantum Mission

India launched the National Quantum Mission with an allocation of ₹6,003.65 crore over eight years, covering four major technology areas: quantum computing, quantum communication, quantum sensing and metrology, and quantum materials and devices.

The programme now connects 152 researchers from 43 institutions across 17 states and two Union Territories through its four thematic hubs and associated technical groups.

Research infrastructure is being developed at IISc, IIT Bombay, IIT Kanpur and IIT Delhi to support indigenous processors, sensors, devices and materials. The Mission is also supporting quantum startups and building specialised training programmes to create a domestic workforce capable of operating across physics, engineering, computing and semiconductor technology.

India Is Keeping Its Options Open

The most interesting feature of India’s quantum-computing strategy may therefore be what it has not done.

India has not declared superconducting qubits the winner.

It has not assumed that semiconductor spin qubits will inevitably inherit the manufacturing advantages of conventional silicon.

It has not decided that photonics, neutral atoms or trapped ions will dominate future quantum machines.

Instead, the National Quantum Mission is allowing researchers to pursue all five approaches while creating shared infrastructure capable of supporting whichever technologies demonstrate the greatest promise.

This makes sense at the present stage of the global quantum race. Every architecture still faces serious engineering obstacles, particularly in reducing errors and scaling from experimental processors towards fault-tolerant machines capable of sustained useful computation.

Some approaches may ultimately dominate particular applications rather than a single technology replacing all others.

Photonic processors could excel in one class of problem, neutral atoms in another and superconducting or semiconductor processors elsewhere. Hybrid architectures may also emerge.

Building the Capability to Choose the Winner

India’s goal is therefore larger than producing a particular number of qubits.

By simultaneously developing superconducting, semiconductor, photonic, neutral-atom and trapped-ion quantum technologies, the country is attempting to acquire the scientific and industrial capability needed to participate in whichever technological pathways ultimately succeed.

The IISc-led Foundation for QC Innovation provides the organisational centre for that strategy, connecting researchers across India while establishing fabrication, testing, startup and cloud infrastructure.

Individual milestones—50 qubits, 100 qubits or 400 atoms—will attract attention as the programme advances. But the more consequential achievement would be creating an Indian ecosystem able to design the qubits, fabricate the processors, build the control systems, write the algorithms and manufacture the specialised equipment required to operate them.

At a moment when no country can yet say with certainty what the dominant quantum computer of the future will look like, India is effectively making five bets at once.

The objective is not simply to guess which architecture wins the global quantum race.

It is to ensure that India possesses the knowledge and infrastructure to build it when the answer becomes clear.

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