Quantum in Japan digest

Quantum technology uses the special rules that govern the extremely small world of atoms and electrons. In our everyday world, objects usually exist in only one state at a time. For example, a coin is either heads or tails. In the quantum world, however, particles can exist in multiple states at once. This is called superposition.

Another important quantum phenomenon is entanglement. When two particles become entangled, their properties are linked. This means that measuring one particle immediately tells you something about the other, even if they are far apart.

The basic unit of quantum information is called a qubit (quantum bit). Unlike a classical bit, which is either 0 or 1, a qubit can exist in a superposition of both 0 and 1. This allows quantum computers to explore many possibilities at the same time.

By using these properties, scientists are developing quantum computers, which may solve certain complex problems faster than conventional computers, and quantum communication systems, which can detect attempts to intercept information.

Although quantum technology is still developing, it is expected to have a major impact on computing, communications, medicine, materials science, and many other fields in the future.

This digest summarizes the latest research, technologies, and trends in the rapidly advancing field of quantum science and technology. It covers a wide range of topics, including quantum computing, quantum communication, quantum sensing, quantum materials, and international collaboration, while also highlighting current research and innovation in Japan in comparison with global developments.

Quantum technology is no longer limited to theoretical physics or laboratory-scale experiments. It is emerging as a key driver of next-generation computing, secure communications, precision measurement, advanced materials discovery, and future industrial competitiveness.

As governments, universities, startups, and major companies around the world accelerate investment and development, understanding both the opportunities and challenges of quantum technologies is becoming increasingly important. The articles below present recent advances, technical challenges, industrial applications, and long-term research goals in Japan. They also explore how quantum technologies intersect with manufacturing, semiconductors, and broader technological and societal transformation.

JFY2026

• Institute for Molecular Science develops 'camera' using single ultracold atom as a lens
• Elucidating the formation mechanism of "germanene," a candidate qubit material
• Kanazawa University develops fundamental technology for qubit position control in diamond
• QST develops microscope achieving both world-leading resolution and high precision

JFY2025

• "Post-quantum cryptography" decoding contest — KDDI Research Inc. and the University of Tokyo achieve world records
• Evaluation of semiconductor colloidal quantum dots using environmentally compatible materials
• Quantization of electric current by surface acoustic waves — University of Osaka discovery raises hopes for new strain-based devices
• NTT and OptQC partner to advance optical quantum computers — Towards one million qubits
• "Gold quantum needles" just three atoms wide — Synthesis through slow reduction of ions: Optical properties also revealed
• First operation of IBM's next-generation quantum computer outside the U.S. begins at RIKEN
• World's first proof that quantum advantage and cryptographic security are equivalent from a cryptographic perspective
• The University of Osaka develops "Zero-level distillation method" — Path to realizing fault-tolerant quantum computers
• Government Council presents measures for the social implementation of quantum technology to Minister Kiuchi
• Fujitsu and RIKEN develop world's highest-performance 256-qubit superconducting quantum computer
• NTT clarifies the connection between independently studied mathematics and physics models — Contributing to quantum computer realization
• "Quantum Computer Disco" and "The Universe: Unread Messages" —New permanent exhibitions at Miraikan

JFY2024

• New quantum infrared spectroscopy method developed by Kyoto University: Realization of compact devices is expected
• Non-classical light pulses used in optical quantum computing platform for the first time by the University of Tokyo, NTT, and NICT
• Quantum technology trends in the Asia-Pacific region
• Quantum Technology Trends in Asia-Pacific: Insights from Japan Science and Technology Agency
• World first general-purpose photonic quantum computer developed by RIKEN and NTT
• High-speed optical quantum state generation 1,000 times faster than conventional methods achieved by the University of Tokyo
• Quantum superposition states of molecular qubits respond to chemicals — One step closer to realizing chemical quantum sensing
• Osaka University, NTT develop new method for realizing quantum simulations — Purification only performed locally
• RIKEN led group discovers quantum light source operating at room temperature at mixed-dimensional heterostructure interfaces
• RIKEN plans for integrated use of quantum computers and supercomputers: Platform research and development project launched

What is quantum technology?

Quantum technology is a field that applies the principles of quantum mechanics to develop new technologies such as computing, communication, and sensing.

What is quantum mechanics?

Quantum mechanics is the branch of physics that describes the behavior of matter and energy at atomic and subatomic scales.

What is quantum computing?

Quantum computing is a type of computation that uses quantum mechanical effects such as superposition and entanglement to solve certain problems more efficiently than classical computers.

What is a qubit?

A qubit is the basic unit of quantum information. Unlike a classical bit, it can exist in a combination of 0 and 1 due to superposition.

What is quantum superposition?

Quantum superposition is a property where a particle can exist in multiple states at the same time until it is measured.

What is quantum entanglement?

Quantum entanglement is a phenomenon where two or more particles become correlated so that the state of one depends on the state of the other, even over long distances.

What is quantum communication?

Quantum communication uses quantum states to transmit information, enabling highly secure communication methods.

What is quantum sensing?

Quantum sensing uses quantum effects to measure physical quantities with extremely high precision.