NTT Bets on Room-Temperature Optical Quantum Computers to Reach a Million Qubits

Japanese telecom and technology giant NTT is pushing a bold strategy in quantum computing: large-scale optical quantum computers that operate at or near room temperature. Partnering with OptQC, NTT aims to build a general-purpose quantum platform that uses photons instead of electrons and does not require vast cryogenic infrastructure. 

From cryogenic racks to photonic platforms

Most leading quantum systems today rely on superconducting or trapped-ion qubits, which require extreme cooling — often colder than deep space — and highly controlled environments. These architectures are powerful but difficult and expensive to scale.

NTT’s approach is different:

• It uses photons as qubits, processed through optical components rather than electronic circuits.

• Photonic systems generate less heat and can, in principle, operate at room temperature, significantly reducing energy consumption and infrastructure cost. 

The company has already demonstrated a general-purpose optical quantum computing platform that can run calculations without external cooling and fits inside a single room—an important contrast to the multi-rack cryogenic setups common today. 

Roadmap: from 10,000 to 1 million qubits

NTT and OptQC outline an ambitious roadmap leading to 2030: 

• Year 1–2: joint hardware–software co-design, early technical studies, and identification of initial use cases with partners.

• Year 3: validation of enterprise workloads such as drug discovery, financial optimization, materials science and climate modeling.

• By 2027: targeting systems with around 10,000 qubits, used as accelerators for AI and large-scale simulations.

• By 2030: aiming for 1 million qubits, coupled with robust quantum error correction, with the goal of handling large, real-world industrial and governmental workloads.

The strategy aligns strongly with Japan’s broader push in photonics and 6G networks, positioning optical quantum computing as a cleaner, more energy-efficient backbone for future AI and telecom infrastructure. 

Why this is a major milestone

This development stands out globally because it tackles three of quantum computing’s biggest pain points at once:

1. Scalability – Room-temperature, photon-based systems could be easier to manufacture and integrate into standard data-center racks. 

2. Energy efficiency – Optical platforms promise drastically lower power usage compared to cryogenic systems, addressing the rising energy cost of AI and HPC. 

3. Industrial strategy – Japan is positioning photonics as a strategic alternative to U.S. and Chinese approaches based mainly on superconducting or neutral-atom hardware. 

Experts still point out that photonic quantum computing faces serious challenges—such as producing near-perfect photon sources and detectors at scale, and engineering effective photon–photon interactions. But if NTT can execute its roadmap, the first million-qubit machine might emerge from a room-temperature optical platform, not a cryogenic lab.

Potential impact for the quantum industry

If NTT’s initiative succeeds, it could:

• Provide a commercially viable, lower-energy alternative to today’s cryogenic machines.

• Deeply integrate quantum accelerators into telecom infrastructure and large AI workloads. 

• Shift part of the global quantum hardware race toward photonic supply chains and optical manufacturing.

For startups and researchers working on photonic quantum tech, this announcement is a strong signal that optical platforms are moving from niche experiments toward mainstream industrial strategies.