Quantum Error Correction Architectures

# Quantum Error Correction Architectures

## Core Concepts

Quantum error correction (QEC) is crucial for building fault-tolerant quantum computers. Unlike classical bits, qubits are susceptible to decoherence and gate errors, leading to information loss. QEC aims to protect quantum information by encoding it redundantly across multiple physical qubits, allowing detection and correction of errors without collapsing the quantum state.

**Key Challenges:**
*   **No-Cloning Theorem:**  Quantum information cannot be perfectly copied, necessitating clever encoding schemes.
*   **Measurement Problem:** Directly measuring a qubit to check for errors collapses its superposition.
*   **Continuous Errors:** Errors aren't just bit flips; they can be phase flips and continuous variations.

## Stabilizer Codes