Planqc

(This profile is one entry in my 2025 series on quantum hardware roadmaps and CRQC risk. For the cross‑vendor overview, filters, and links to all companies, see Quantum Hardware Companies and Roadmaps Comparison 2025.)

Introduction

Planqc is a Munich-based quantum computing startup (founded in 2022 as a Max-Planck-Institute spin-off) developing a neutral-atom quantum computing platform. The company’s core approach is to store quantum information in individual ultra-cold atoms that are trapped in optical lattices – effectively using nature’s identical atoms as qubits. By leveraging techniques from atomic clocks, high-resolution quantum gas microscopes, and fast Rydberg-mediated gates, planqc aims to build scalable, digital quantum processors operating at or near room temperature. This distinguishes planqc’s platform from superconducting or ion-trap qubit technologies that require specialized chips and cryogenics.

With strong backing from German research institutions and investors, planqc has set out an ambitious roadmap toward universal, fault-tolerant quantum computers comprising thousands of qubits, positioning itself as a European leader in neutral-atom quantum hardware.

Milestones & Roadmap

No published roadmap.

Planqc’s journey began in April 2022 with its founding by scientists from the Max Planck Institute of Quantum Optics (MPQ) and LMU Munich, making it the first startup emerging from the Munich Quantum Valley hub. An initial seed financing of €4.6 million was raised in mid-2022 to develop a highly scalable quantum computer based on atoms in optical lattices. By 2023, planqc had secured a major contract under the German Aerospace Center’s Quantum Computing Initiative (DLR QCI): a €29 million award to build a 100-qubit neutral-atom quantum computer for installation at DLR’s Innovation Center in Ulm. This project, dubbed DiNAQC (Digital Neutral-Atom Quantum Computer), represents the first sale of a gate-based neutral-atom quantum system in Europe. Strategic partners including Menlo Systems (for ultra-stable laser systems) and ParityQC (for software and architecture design) joined this effort. According to planqc, the 100-qubit demonstrator is targeted to be operational by spring 2027, aligning with Germany’s action plan to have a 100-qubit digital quantum computer by end of 2026.

Momentum accelerated in 2024. In July 2024, planqc closed a €50 million equity financing round to expand its team and R&D capacity. Then in late 2024, the company was selected to lead a €20 million federally funded project to build a 1,000-qubit neutral-atom system at the Leibniz Supercomputing Centre (LRZ) in Garching. This LRZ project, called MAQCS (Multicore Atomic Quantum Computing System), aims to deploy a universally programmable quantum co-processor exceeding 1,000 qubits by circa 2027. Notably, MAQCS features an innovative multi-core architecture: two interlinked 500-qubit modules (cores) operating in parallel for higher throughput. The multi-core design will allow one core to reset (e.g. reload atoms) while the other continues computation, thereby reducing latency and boosting overall execution speed. Both the 100-qubit DLR system and the 1000-qubit LRZ system are planned for integration into HPC environments, in Ulm and Munich respectively, enabling users to access them via cloud interfaces or as quantum accelerators within classical supercomputers. According to planqc’s leadership, these milestones mark stepping stones toward industry-relevant quantum advantage and put Germany’s quantum hardware roadmap on par with global efforts.

Focus on Fault Tolerance

From its inception, planqc has emphasized a path to fault-tolerant quantum computing, recognizing that merely scaling qubit count is not enough without error correction. The company’s neutral-atom platform leverages intrinsically identical qubits and precision laser control to minimize certain error sources – for example, unlike superconducting qubits that vary in fabrication, “every atom is the same from the ground up,” reducing calibration errors. Moreover, operation at room temperature avoids cryogenic infrastructure and some noise modes of solid-state devices. Still, achieving fault tolerance requires robust error mitigation and correction. Planqc’s team has explicitly acknowledged this, with CTO Sebastian Blatt noting that the DLR 100-qubit machine will take the first steps toward quantum error correction in a practical setting. The long-term strategy involves grouping multiple physical atoms into one logical qubit and introducing auxiliary qubits that act as “error sensors”, akin to canaries in a coal mine, to detect and correct errors without disrupting the computation. In essence, many physical qubits will redundantly encode quantum information so that if one atom’s state flips or a loss occurs, the encoded logical qubit can be preserved.

Concrete progress has been made on error mitigation techniques at the hardware level. In October 2024, a joint team from MPQ and planqc demonstrated a 1200-atom quantum register operating continuously for over an hour, overcoming a key scalability obstacle. They achieved this by continually reloading lost atoms from a reservoir into the optical lattice, thereby stabilizing a large qubit array against atom loss – a form of active error mitigation crucial for long runtimes. Additionally, planqc’s partnership with laser specialist Menlo Systems is providing ultra-narrow-linewidth lasers (sub-hertz) and optical frequency combs that enable extremely coherent control of atomic qubits. Such high spectral purity in the laser system reduces phase noise and operational errors during gate operations. Together, these efforts indicate a focus on improving fidelity per qubit and per gate, which is essential groundwork for demonstrating logical qubits. While full fault tolerance (with error rates below thresholds and logical qubits outlasting physical ones) remains a longer-term goal, planqc is integrating error correction concepts early. The 1000-qubit MAQCS project explicitly emphasizes advancing quantum error correction as a deliverable, underscoring that planqc’s roadmap is oriented toward eventually realizing reliable, fault-tolerant computation.

CRQC Implications

Planqc’s drive toward large-scale, error-corrected quantum hardware holds important implications for reaching cryptographically relevant quantum computing (CRQC) capabilities. A “CRQC” is generally defined as a quantum computer powerful enough to break contemporary cryptographic schemes (e.g. RSA encryption) by running algorithms like Shor’s – which in practice is estimated to require on the order of millions of physical qubits with full error correction. Planqc’s current projects (100 to 1000 qubits) are still far below that threshold, but they represent critical incremental progress. By pioneering a 1000-qubit neutral-atom machine integrated with an HPC center, planqc and its partners are demonstrating the feasibility of scaling quantum processors into the “kilojubit” realm and operating them in real-world computing environments. This paves the way for tackling more complex computational problems, including small instances of classically intractable cryptographic challenges. Indeed, planqc’s CEO has highlighted cryptography as one of the industries that stands to benefit from more powerful quantum computers.

Even at 1000 qubits, a device would not be able to crack standard RSA encryption; however, it could be used to prototype the quantum algorithms that someday will. Planqc’s emphasis on fault tolerance and error correction in these early machines is especially relevant to CRQC – any cryptographically relevant algorithm will demand prolonged, accurate quantum operations that only an error-corrected quantum computer can supply. The planqc MAQCS architecture, with parallelizable cores and improved duty cycle, can be seen as a stepping stone towards the architectures needed for CRQC. Moreover, by integrating quantum processors with classical supercomputers via the Munich Quantum Software Stack (MQSS) and similar frameworks, planqc is helping build the hybrid classical-quantum infrastructure that would harness a future CRQC for practical use. In strategic terms, planqc’s government-backed projects signal national interest in achieving CRQC-scale technology domestically. Germany’s investment in neutral-atom qubits complements global efforts and could ensure that as quantum computing approaches cryptographically relevant scales, there is European-developed hardware at the forefront. In summary, while planqc’s near-term systems will mainly address problems in optimization, materials, or pharma, their technology differentiators – long coherence atoms, scalable lattices, and error mitigation – are directly on the critical path toward a CRQC in the longer run. The firm’s progress thus contributes to the timeline by which truly cryptography-breaking quantum computers might become a reality, underlining the need for parallel advancement in post-quantum cryptography.

Modality & Strengths/Trade-offs

Planqc’s hardware modality is ultracold neutral atoms in optical traps, which comes with distinct advantages for scalability as well as its own technical trade-offs. In planqc’s design, hundreds to thousands of atoms (e.g. strontium atoms, leveraging atomic clock transitions) are held in a regular grid by an optical lattice – often likened to trapping atoms at the sites of an “egg carton” made of light. Each atom serves as a qubit, typically using two internal electronic states to represent |0⟩ and |1⟩. Because all atoms of a given element are identical and immune to fabrication defects, the qubits are highly uniform by nature. This homogeneity contrasts with solid-state qubits (superconducting circuits) where each qubit can have slightly different characteristics, necessitating calibration and leading to correlated errors. Moreover, neutral atoms have no net charge, so unlike trapped ions, they do not strongly repel each other; this allows dense packing of many qubits without the Coulomb interaction limits that ion-trap systems face. Room-temperature operation is another strength – aside from needing vacuum chambers and laser systems, the neutral-atom setup does not require dilution refrigerators or cryostats, simplifying some engineering aspects and power requirements. In principle, optical trapping techniques can readily scale to 2D arrays of hundreds or more atoms, as evidenced by research prototypes (the MPQ-planqc team recently sustaining 1200 atoms in one lattice). This high native qubit count and the possibility of reloading atoms make the platform attractive for reaching the large system sizes needed for quantum advantage.

For two-qubit gate interactions, planqc (like other neutral-atom efforts) employs Rydberg-state mediated gates: lasers briefly excite two selected atoms to high-energy Rydberg states, causing a strong dipole-dipole interaction that entangles their states (the Rydberg blockade mechanism). These gates can be performed in parallel on different pairs, and typical Rydberg gate times are on the order of a few microseconds – relatively fast compared to, say, ion-trap gates (tens of μs) though slower than superconducting gates (tens of ns). Single-qubit operations on neutral atoms (using microwaves or Raman laser pulses) can be extremely high-fidelity, benefiting from the narrow atomic transitions borrowed from atomic clock techniques. Indeed, experiments with strontium qubits have demonstrated coherence times in the tens of milliseconds range and dozens of coherent Rabi oscillations without significant decay. These attributes imply that neutral-atom qubits can have long memory and potentially low error rates if controlled with state-of-the-art lasers.

The trade-offs, however, include the complexity of laser control and addressing: to individually manipulate one atom among thousands, tightly focused beams or advanced optical modulators are required. Planqc identified precise “spotlighting” of each atom with a laser as a major challenge – qubits must be spaced closely (for strong interactions), yet the laser focusing must avoid illuminating neighbors, or else crosstalk errors occur. In a large array (with typical atom spacing a few micrometers), this pushes optical engineering to its limits. Planqc’s team has solved this in lab conditions using custom optics, but translating that to a compact, reliable device is part of their ongoing development.

Another consideration is that while neutral atoms can be arrayed in 2D (suitable for implementing error-correcting codes like the surface code on a grid), the natural interactions are generally short-range. Scaling beyond a single lattice zone may require linking multiple atom arrays (the rationale for planqc’s multicore architecture) or shuttling atoms – approaches that add architectural complexity.

Finally, the current neutral-atom setups involve significant infrastructure (vacuum chambers, multiple laser sources, high-NA imaging systems). Miniaturization is non-trivial; even though no cryogenics are needed, the optical hardware must be stabilized to micron precision. Planqc’s second major project explicitly targets engineering the system into standard server racks, including fitting the vacuum chamber and lasers into a compact footprint. In summary, planqc’s neutral-atom modality offers strong scalability and qubit uniformity, with trade-offs centered on control precision and system integration. The company’s bet is that these challenges can be overcome with cutting-edge photonics and clever engineering – yielding a platform that can outperform or outscale more mature modalities in the long run.

Track Record

Although still an early-stage company, planqc’s track record so far reflects a blend of deep scientific accomplishments and rapid execution on deliverables. The founding team (Dr. Sebastian Blatt, Dr. Johannes Zeiher, Dr. Alexander Glätzle, and colleagues) brought decades of neutral-atom research experience – including breakthroughs in atomic clock technology and quantum simulation – directly into the venture. This expertise has translated into tangible technical progress within just a few years. Notably, planqc contributed to a 2024 demonstration of a continuously operating 1200-atom array, solving the atom loss problem by active reloading. Such a result, achieved in collaboration with MPQ’s Quantum Many-Body Systems group, set a new benchmark for stable qubit array size and showcases planqc’s ability to tackle key scalability issues.

On the qubit control front, the team has also pioneered techniques for Strontium atomic qubits – for instance, coherently controlling qubits encoded in metastable states with high fidelity (exceeding 60 Rabi cycles) and achieving coherence times on the order of 10-100 ms. These technical milestones, though stemming from academic work, feed directly into planqc’s hardware design.

On the commercial and strategic side, planqc has an impressive record of securing support. By 2023, it had won two major government-backed projects: the DLR contract for a 100-qubit system (Germany’s first dedicated purchase of a neutral-atom quantum computer) and the BMBF-funded 1000-qubit MAQCS consortium. Successfully obtaining these highly competitive contracts indicates strong confidence from institutional stakeholders in planqc’s technology roadmap. In parallel, planqc attracted substantial venture capital – €50 million in Series A funding (led by UVC Partners, Speedinvest, and others) by mid-2024 – bringing its total financing to roughly €87 million when combined with public project grants.

The company has also built out its ecosystem through partnerships: collaborating with ParityQC to implement advanced compilers/architectures and with Menlo Systems to integrate state-of-the-art laser solutions. Planqc’s systems are poised to be deployed at prominent German computing centers (Ulm and LRZ Munich), which will provide early testbeds for real applications. While the first planqc machines are not yet publicly accessible as of 2025, the company plans to deliver systems to its institutional partners by 2026-2027 and eventually offer cloud access to its quantum computers that it operates itself. This dual model, selling turnkey quantum hardware and providing quantum compute-as-a-service, reflects a strategic vision for scalability and revenue once the technology matures. In summary, planqc’s track record thus far is marked by scientific innovation, successful fundraising, and on-track execution of its initial roadmap. The startup has rapidly transitioned from lab prototypes to constructing deliverable quantum hardware, all while assembling a 50+ member team and an ecosystem to support its ambitious goals.

Challenges

Despite its strong progress, planqc faces a number of technical and strategic challenges on the road to a scalable, fault-tolerant quantum computer. Chief among these is the precision control problem inherent in neutral-atom architectures: focusing laser beams onto individual atoms in a dense array without inducing errors on neighboring qubits. As Sebastian Blatt explained, atoms must be very close together to interact, making it “at the limit of what is physically possible” to optically address one without affecting another. Any slight misalignment causes crosstalk, which can introduce gate errors. Planqc will need to continue refining its optical delivery systems – potentially using advanced beam-shaping, feedback stabilization, or novel addressing schemes – to maintain high fidelity as the qubit count grows.

Another technical hurdle is the “miniaturization” and engineering of the full system. Currently, a neutral-atom quantum computer at lab scale involves multiple optical tables’ worth of lasers and control electronics. Planqc’s goal is to condense this into robust, rack-mounted modules suitable for data center environments. Achieving this requires significant engineering of vacuum hardware, laser packaging, and thermal/mechanical stability. The company has acknowledged this by hiring engineers and treating the MAQCS 1000-qubit project partly as an integration challenge to fit the vacuum chamber and optics into a compact form factor. It’s a non-trivial task that will test planqc’s transition from a research prototype to an industry-grade product.

Scaling to larger qubit numbers while maintaining performance will also test the limits of the neutral-atom approach. Although neutral atoms avoid some scaling bottlenecks of other modalities, maintaining coherence and calibration across 1000+ qubits is uncharted territory. Issues like laser phase noise, motional heating of atoms, and background gas collisions could become more pronounced and will need meticulous control (hence the ultra-stable lasers and vacuum improvements in planqc’s design).

On the algorithmic side, as planqc introduces error correction, a challenge will be managing the overhead of error-correcting codes. Even a moderate-distance surface code could consume hundreds of physical atoms per logical qubit. Planqc will need to demonstrate that their multi-core architecture and any error mitigation can handle this overhead efficiently, and that the trade-off of using many physical qubits is feasible given their scaling advantages.

In broader terms, planqc operates in a competitive and rapidly evolving landscape. Neutral-atom quantum computing is also being pursued by international peers (e.g. Pasqal in France, QuEra in the US), and other modalities (superconducting, ion traps, photonics) continue to advance. It remains uncertain which platform will ultimately prevail or reach fault-tolerance first. Planqc thus faces the strategic challenge of delivering on its performance promises on a similar timeline as larger competitors. This includes meeting the German government’s milestones (100 qubits by 2026, 1000 by 2027), which are aggressive deadlines. Any significant delays or technical setbacks could impact funding and support, especially since government and industry users have expectations for integration into real workflows. Lastly, the task of building a skilled workforce is nontrivial – quantum engineering requires niche talent. Planqc has grown to around 50 employees, but scaling further (to tackle both R&D and product engineering in parallel) will be necessary and competitive in the current quantum talent market.

In summary, planqc must navigate a tightrope of innovating at the forefront of neutral-atom physics while executing as a systems engineering venture. The challenges of precision control, system integration, error correction overhead, and market competition are substantial. However, the company’s prior accomplishments and backing suggest it is aware of these hurdles and is systematically addressing them. Overcoming these challenges will be crucial for planqc to validate its platform’s promise: a path to scalable, fault-tolerant quantum computing built “atom by atom.”