The Dawn of a New Era in Electron Microscopy

Japan's National Institutes for Quantum Science and Technology (QST), in collaboration with Tohoku University, has unveiled a groundbreaking advancement in scientific imaging: the 2D-RIXS microscope. Announced on April 13, 2026, this instrument achieves both world-leading spatial resolution of 1 micrometer and ultra-high energy resolution of approximately 17 millielectronvolts (meV) simultaneously. Resonant Inelastic X-ray Scattering (RIXS), the core technique, traditionally excelled in energy precision but lagged in spatial detail. This innovation bridges that gap, enabling researchers to visualize electron behaviors—charge, spin, and orbital states—at microscopic scales within materials.

The development stems from meticulous work at NanoTerasu, a state-of-the-art 3 GeV synchrotron radiation facility in Sendai, operational since 2025. QST researchers Kohei Yamamoto and Chief Researcher Jun Miyawaki, alongside Tohoku University's Assistant Professor Hakuto Suzuki, published their findings in the Journal of Synchrotron Radiation (DOI: 10.1107/S1600577526000573), marking a pivotal moment for quantum materials research.

Background: QST and NanoTerasu's Role in Quantum Research

QST, established to pioneer quantum technologies, focuses on quantum life sciences, energy, and information processing. NanoTerasu, a collaborative project between QST and Tohoku University, delivers intense soft X-rays ideal for RIXS experiments. Prior to this, QST's 2D-RIXS spectrometer, introduced in 2025, set the world record for energy resolution but sacrificed spatial mapping by aggregating signals for sensitivity.

This limitation meant RIXS provided only averaged electron data across samples, insufficient for heterogeneous quantum materials or nanoscale devices. The new microscope transforms RIXS into a true imaging tool, akin to an electron-state microscope, opening doors for precise analysis in Japan's burgeoning quantum sector.

Decoding RIXS: From Spectroscopy to Microscopy

Resonant Inelastic X-ray Scattering (RIXS) probes material electron states by tuning soft X-rays (around 850 eV here) to absorption edges, analyzing scattered photons' energy loss. It reveals excitations like magnons or plasmons invisible to other methods. Traditionally, detectors summed pixels for signal strength, blurring spatial info.

The 2D-RIXS approach retains two-dimensional detector data pre-summation. Key steps include:

• Illuminate sample with monochromatized X-rays from NanoTerasu.
• Capture scattered X-rays on a high-resolution 2D detector via grating and mirror optics.
• Ray-trace each photon's path backward using optical simulations to pinpoint origin within the sample.
• Reconstruct images mapping electron states at 1 μm resolution.

This single-shot method avoids scanning, minimizing damage and time.

Overcoming Technical Hurdles

Achieving dual resolutions demanded novel optics and algorithms. The team optimized diffraction gratings and imaging mirrors for ~17 meV energy precision while resolving 1 μm spaces. Challenges included photon tracing accuracy amid optical aberrations and weak signals from micro-areas.

Through iterative simulations and experiments, they back-calculated positions with unprecedented fidelity. Validation used a nickel (Ni) thin-film pattern on silicon mimicking NanoTerasu's logo, selectively probing Ni 3d electrons. The resulting map vividly depicted electron distributions, confirming viability for device-scale analysis.

Demonstration: Imaging Quantum States in Action

In proof-of-concept tests, the microscope imaged Ni patterns under Ni L-edge excitation. Colors in reconstructions represented Ni 3d electron intensities, revealing spatial variations tied to spin or orbital orders. This surpasses prior RIXS by 20-fold in spatial detail (400x pixels), per QST reports.

Chief Researcher Miyawaki noted, "High precision (energy resolution) and positional data (spatial resolution) were once incompatible, but back-calculating X-ray photon spaces enabled this 2D-RIXS microscope. It will contribute to diverse solid-state materials like spintronics."

Photo by Daniel Romero on Unsplash

NanoTerasu: Japan's Synchrotron Powerhouse

NanoTerasu, launched in 2025, provides brilliant soft X-rays for nanoscale studies. Beamline BL02U hosts the 2D-RIXS setup, now open to global users. This facility accelerates Japan's quantum leadership, complementing SPring-8 and Photon Factory.

For higher education, it offers Tohoku students hands-on access, fostering next-gen talent in materials physics.

Applications in Quantum Materials and Beyond

The microscope targets quantum materials where electron states dictate properties. Key uses:

• Spintronics: Map spin waves in devices for low-power computing.
• Superconductors: Visualize high-Tc cuprates' pairing mechanisms.
• Nanodevices: Inspect heterostructures for next-gen semiconductors.
• Energy Materials: Analyze battery cathodes or catalysts at microscales.

Industries like electronics and energy stand to benefit, with QST emphasizing spintronics and info devices. For details, see the official QST announcement (QST Press Release).

Implications for Japan's Research Ecosystem

This bolsters Japan's quantum strategy under MEXT, positioning QST/Tohoku as global leaders. Universities gain tools for PhD training, publications, and industry ties. NanoTerasu's open access democratizes cutting-edge research, aiding SMEs in precision materials.

Amid global quantum races (US Quantum Economic Development Consortium, EU Quantum Flagship), Japan's edge in RIXS sharpens competitiveness.

Stakeholder Perspectives and Challenges

Academics praise the leap: spatial mapping unlocks 'where' questions in quantum phenomena. Industry eyes spintronic prototypes. Challenges remain: scaling to sub-micron, harder samples, data processing.

QST plans enhancements for broader elements, integrating machine learning for faster reconstructions.

Future Horizons: Quantum Tech Revolution

Expect integrations with cryo-EM or STEM for multimodal imaging. In education, VR simulations of RIXS could train students. By 2030, this may underpin faultless quantum chips, per QST visions.

Japan's investment yields: from basic science to societal impact, exemplifying higher ed's role.

Photo by Possessed Photography on Unsplash

Japan's Quantum Research Landscape

QST anchors Moonshot R&D Goal 9 (quantum tech), with ¥100B+ funding. Tohoku's IMRAM complements, training 500+ quantum experts yearly. This microscope elevates NIRIM-QST collaborations.

Comparative table highlights the dual breakthrough.