Measurement-based quantum computing

Definition

Measurement-based quantum computing is a model of quantum computation where the computation is driven by measurements on entangled quantum states, specifically cluster states. This approach utilizes the properties of entanglement and measurement to perform quantum operations, making it a different paradigm compared to traditional gate-based quantum computing. In this model, the initial state is prepared as a highly entangled state, and the subsequent computations occur through a sequence of measurements that transform this state into desired outcomes.

5 Must Know Facts For Your Next Test

1. In measurement-based quantum computing, the computation begins with the preparation of a cluster state, which is a resource for performing computations through measurements.
2. The sequence of measurements performed on a cluster state can lead to different computational paths and outcomes depending on the measurement results.
3. This model allows for fault-tolerant quantum computation, as it can be designed to correct errors during the measurement process.
4. Measurement-based quantum computing can be implemented using various physical systems, including photons and atoms, demonstrating its versatility across different platforms.
5. The concept originated from research aimed at understanding how measurements affect quantum systems and how this could be harnessed for computational purposes.

Review Questions

• How does measurement-based quantum computing differ from traditional gate-based quantum computing?
  • Measurement-based quantum computing differs fundamentally from traditional gate-based quantum computing in that it relies on measurements of entangled states rather than logical gates to perform computations. In this model, an initial cluster state is prepared, and operations are completed by sequentially measuring parts of this state. In contrast, gate-based models manipulate qubits directly using specific gates to achieve computational tasks.
• Discuss the role of cluster states in measurement-based quantum computing and their significance in this model.
  • Cluster states serve as the foundational resource for measurement-based quantum computing. These highly entangled states enable complex computations to occur through measurements without needing to apply gates directly. The arrangement and connections between qubits in a cluster state dictate how measurements will influence the outcome, making them crucial for determining computational paths and enabling efficient processing in this framework.
• Evaluate the advantages and challenges of using measurement-based quantum computing for practical applications.
  • Measurement-based quantum computing presents several advantages, including inherent fault tolerance and flexibility in implementation across various physical systems. It allows for more adaptive computation based on measurement outcomes. However, challenges include managing the complexity of preparing cluster states and performing measurements accurately. Ensuring high fidelity in these processes is critical for achieving reliable results in practical applications, highlighting the need for ongoing research to optimize these aspects.

Related terms

Cluster state: A specific type of entangled state used in measurement-based quantum computing that can be represented as a graph where each vertex corresponds to a qubit and edges represent entanglement.

Entanglement:

A quantum phenomenon where two or more particles become interconnected in such a way that the state of one particle cannot be described independently of the state of the other(s), regardless of the distance separating them.

Quantum gate: A basic quantum circuit operating on a small number of qubits, which performs a unitary operation and is fundamental to traditional gate-based quantum computing.