Quantum Error Correction and Fault-tolerant Quantum Computing

Quantum error correction (QEC), providing systematic ways for protecting qubits from errors, is essential to achieve fault tolerance in building scalable quantum computing systems. QEC has been becoming the major keyword of quantum technology and research over the past few years with several experimental breakthroughs. In this article, I introduce the basic theory of QEC with all relevant concepts, recent experimental achievements, and technological challenges.