Breaking New Ground with the Tesseract Code
We’ve achieved another milestone in our journey to develop scalable, fault-tolerant quantum computing technologies — the successful implementation of the Tesseract code.
The Tesseract code sets a new benchmark for quantum error correction. This is the first-ever demonstration of quantum error correction using the Tesseract code showcasing improvements over single-mode GKP qubits and unveiling new possibilities for multimode bosonic codes.
What is the Tesseract Code?
Nord Quantique is pioneering quantum computer development using bosonic codes, a groundbreaking approach that exploits the natural redundancy of photons (bosons) within quantum modes. This method enables built-in error resilience—a unique capability unattainable by conventional qubit-based systems. Unlike traditional architecture reliant on discrete two-level systems (aka qubits), bosonic codes utilize the continuous spectrum of photon states in quantum modes to encode information.
The Tesseract code is a specific bosonic code used to help protect quantum information from errors. The code arranges the quantum state of the photons in a structure similar to a four-dimensional cube, or tesseract. This approach allows the code to spot errors more efficiently than other methods. By focusing on photonic redundancy, Nord Quantique’s platform addresses a critical bottleneck in quantum computing, positioning it at the forefront of scalable, fault-tolerant quantum technology.
How is Nord Quantique using the Tesseract code?
We view bosonic codes as a transformative solution for quantum error correction, offering a direct pathway to construct quantum computers from logical qubits—bypassing the inefficiencies of conventional systems. Unlike mainstream platforms, which demand thousands of physical qubits to create a single error-resistant logical qubit, bosonic codes eliminate this colossal overhead. Traditional architectures face severe scalability challenges, requiring data-center-scale infrastructure and incurring prohibitive operational costs to achieve performance suitable for practical quantum computing applications.
By leveraging bosonic codes, Nord Quantique sidesteps these barriers, enabling a streamlined path to fault-tolerant quantum systems. This approach not only reduces hardware complexity but also accelerates the transition from experimental prototypes to utility-scale quantum systems.
Advancing Error Correction with Multimode Bosonic Codes
Bosonic codes harness photons in quantum modes (bosonic modes) to encode quantum information efficiently while providing the means to correct natural errors through inherent photon redundancy. While single-mode GKP codes have demonstrated promising error resilience, their limitations in real-world scalability demand more robust architectures. Multimode codes address this gap by distributing logical information across interconnected bosonic modes, enhancing both stability and fault tolerance.
Nord Quantique superconducting multimode cavity
Nord Quantique’s Breakthrough
By embedding a logical qubit into two bosonic modes via the Tesseract code, Nord Quantique leverages higher-dimensional phase space to amplify error correction. This design simultaneously combats photon loss and sharpens precision in error detection, addressing two critical vulnerabilities in photonic systems. The Tesseract code’s structure not only improves hardware-level reliability but also streamlines control over quantum states. With the right parameters, the Tesseract code is expected to surpass single mode GKP qubits by order of magnitude. (see our technical paper to learn more).
Key Advancements
Hardware-efficient scalability: Nord Quantique demonstrates automonous quantum error correction on the tesseract code. By encoding logical qubits in multiple bosonic modes, the Tesseract code is designed to achieves higher error thresholds while maintaining a compact hardware footprint—a stark contrast to the thousands of qubits needed in conventional qubit architectures.
Real-time error insights: The addition of more modes allows for added functionalities in error detection. In the case of Tesseract, the suppression of Leakage errors (where the qubit leaves the encoding space) is realized by getting real-time insights based on a confidence scored obtained by mid-circuit measurements.
Path to FTQC: The Tesseract code’s design highlights how multimode bosonic codes can be used to gain functionalities in quantum error correction and bypass the inefficiencies of stepwise scaling. Compressing QEC capabilities into fewer physical components, the Tesseract code redefines the path toward fault tolerant quantum computers.
Tesseract Code: Accelerating Fault-Tolerant Quantum Computing
The Tesseract code marks a critical milestone in Nord Quantique’s roadmap by enabling logical qubits built directly with error correction—eliminating the need to scale physical qubits first. As a higher-dimensional bosonic code, it enhances quantum error correction (QEC) performance without expanding hardware complexity, leveraging multidimensional phase space to embed richer error-detection structures. This approach bypasses the traditional trade-off between computational accuracy and system size, delivering fault tolerance with minimal physical resources.