The Decade of Fault-Tolerant Quantum Computing: From Threshold Crossing to Scalable Logical Qubits

Quantum error correction (QEC) has transitioned from a theoretical promise to an experimental reality, with recent demonstrations of below-threshold logical qubits marking a turning point in the quest for fault-tolerant quantum computing. Over the past five years, breakthroughs in surface code implementations, low-latency decoders, and improved physical qubit fidelities have brought us to the brink of scalable logical qubit systems. Yet the road to practical quantum advantage remains steep: correlated noise, cryogenic control complexity, and the resource overhead of magic state distillation still pose major barriers. Here, we synthesize recent progress across superconductng, trapped-ion, and neutral-atom platforms, assess the state-of the-art in topological and LDPC codes, and highlight engineering challenges that must be overcome to achieve systems with thousands of logical qubits. We argue that the 2025-2035 decade will be decisive for quantum computing, with success hinging on co-design of hardware, software, and algorithms. This perspective outlines a roadmap for the next generation of fault tolerant systems and discusses the societal and economic implications of entering the era of practical quantum advantage.