SmaraQ Project Adds On-Chip Photonics to Quantum Computing
German SmaraQ Project Uses Quantum Optics on Chip for Scalable Ion Traps
SmaraQ, a new German research group, is miniaturising optical devices to govern ion-trap qubits, scaling quantum computer hardware. The German Federal Ministry of Research, Technology, and Space finances this September 2025–2028 project. Lithographically produced on-chip components could enable powerful and compact quantum processors instead of massive free-space optics arrays.
Like the Smaragdkolibri (Blue-tailed Emerald Hummingbird), the project is small and accurate in UV light sensing and navigation. To preserve Germany and Europe's quantum technological sovereignty, SmaraQ is building a robust domestic supply chain.
Addressing Scalability Bottleneck
Among the most promising quantum designs are ion-trap quantum computers. Qubits made of naturally occurring charged atoms (ions) have unparalleled coherence times and qubit control accuracy. Due to their stability and accuracy, ion-trap devices have accurately demonstrated complex quantum algorithms. QUDORA Technologies GmbH's NFQC (Near-Field Quantum Control) technology, vital to their products, shows how this method can meet high performance requirements.
However, scaling these technologies is a major industry hurdle. Researchers must increase qubits from tens to hundreds or thousands to solve commercially critical challenges. Existing designs require many laser beams to precisely target each qubit for initialisation, cooling (to keep the ion stationary and suspended), and quantum gate operations.
These crucial optical processes are performed by large, complicated optical benches outside the vacuum chamber housing the ions. These benches contain mirrors, lenses, beam splitters, modulators, and hundreds of other delicate parts that must be aligned within micrometres. The size and complexity of this apparatus limit the processor's physical size and the amount of qubits it can efficiently control. Packing hundreds of laser beams into a processor assembly causes rapid technical issues, preventing industrial growth.
Precision on Chip: Integrated Solution
SmaraQ addresses this complex problem with advanced photonic integration. Advanced UV waveguides and photonic elements that can be printed directly onto ion-trap chips are the key technological achievement. UV light is needed to manage trapped ions' energy levels.
Waveguide devices at the nanometre scale replace heavy, free-space optics for distant light transmission in the revolutionary method. Hair is thousands of times thicker than these structures. “On-chip integration represents the path forward for ion-trap quantum computing,” said QUDORA Photonics Head Maik Scheller. He stated that the group is constructing nanometre waveguide devices 10 thousand times smaller than a human hair to deliver light to ion qubits. Dr. Scheller calls the switch from free-space optics to integrated photonics “the single most important architectural change needed to unlock true scalability”.
Materials science is crucial to the project. The consortium focusses on aluminium nitride (AlN) and aluminium oxide (AlO₃) for their transparency and stability at UV wavelengths for ion-qubit manipulation. Importantly, lithography, the same high-precision fabrication technology used in the semiconductor sector, can mass-produce identical, superior optical components. This technology makes manually aligning hundreds of optical pieces cheaper and easier.
Cooperation and Domestic Supply Chain To succeed, SmaraQ needs the complementary talents of its three top German partners, who form a vertical supply chain for supporting technology:
As system integrator and project coordinator, QUDORA Technologies GmbH manages the architecture and brings the technology to market. Their extensive knowledge of ion-trap quantum system specifications ensures that the parts work properly in quantum processors.
The Fraunhofer IAF focusses on crucial materials science. Fraunhofer IAF epitaxially grows thin-film AlN wafers to excellent quality. AlN is the primary substrate for UV waveguides, and its world-class quality is crucial for high-fidelity light delivery and light loss reduction.
AMO GmbH: Using nanotechnology, AMO designs and manufactures the chips' intricate photonic components. Accurate lithographic patterning and etching are needed to transform the unprocessed AlN/AlO₃ layer into precise waveguide structures for UV light.
This alliance aims to strengthen Germany's supply chain for these critical supporting technologies. The SmaraQ project develops materials, fabrication methods, and system integration knowledge locally to support the BMFTR's goal of technological sovereignty in key quantum supply chains.
Future Strategic Implications
Following the BMFTR's clear assertion that industrial translation of quantum research is a national priority, the SmaraQ project is a measured investment in Germany and Europe's high-tech future.
By integrating complex optical control systems onto a semiconductor, ion-trap quantum computers become economically viable. By substantially reducing quantum hardware size, power consumption, and manufacturing complexity, SmaraQ accelerates the transfer of these powerful devices from research labs to commercial deployment. This breakthrough enables the production of scalable quantum processors with higher reliability and throughput, like silicon chips.
If successful, on-chip photonic control will enable fault-tolerant quantum computation. To execute complex error correction codes, fault tolerance requires a huge number of qubits and precise, customised control over each one. SmaraQ's contribution is vital to the global endeavour to develop practical quantum technology. Germany will lead quantum sensing and quantum computing, which often require precision optical control systems, if this technology is successfully implemented.
SmaraQ was a turning point in ion-trap quantum computing. Using integrated photonics to solve optical scalability, the German consortium could transform one of the most promising quantum technology platforms. It is expected that the UV integrated photonic platform will enable unprecedented scaling of ion-trap quantum processors from enormous laboratory systems to tiny, reliable, and economically practical devices. This miniaturization and precision engineering effort is crucial to quantum computation's long-term potential.