Measurement-based quantum computing

Definition

Measurement-based quantum computing is a model of quantum computation that relies on making measurements on a highly entangled state, often referred to as a cluster state. In this model, the computation proceeds through a series of measurements that determine the outcomes of quantum gates applied to qubits. This approach emphasizes the role of measurement in driving the computation, contrasting with traditional gate-based quantum computing methods.

5 Must Know Facts For Your Next Test

1. In measurement-based quantum computing, the initial preparation of a cluster state is crucial, as it sets the foundation for subsequent measurements and computations.
2. Measurements can be adapted dynamically based on previous results, allowing for a more flexible approach compared to traditional gate-based computing.
3. The concept of measurement-based computing highlights the non-locality and contextuality inherent in quantum mechanics, as the outcome of measurements can depend on the entire state of the system.
4. This model is particularly well-suited for photonic systems, where qubits can be represented by properties of photons such as polarization or phase.
5. Measurement-based quantum computing has been shown to provide universal quantum computation, meaning it can perform any calculation that a traditional quantum computer can, but through a different operational framework.

Review Questions

• How does measurement-based quantum computing differ from traditional gate-based quantum computing in terms of operational processes?
  • Measurement-based quantum computing differs from traditional gate-based methods by using a highly entangled cluster state as the starting point for computations. Instead of applying sequences of quantum gates to manipulate qubits directly, it involves making measurements on the entangled state to determine the outcomes and drive the computation forward. This shift emphasizes the role of measurement in quantum processing, showcasing a unique approach to harnessing quantum properties.
• What role does entanglement play in measurement-based quantum computing and how does it influence computational outcomes?
  • Entanglement is fundamental to measurement-based quantum computing as it creates the cluster states necessary for computation. These entangled states enable correlated measurements that influence one another across qubits. The interconnected nature of entangled particles means that measuring one qubit can have immediate effects on others, leading to outcomes that depend on the entire system rather than individual qubits alone. This property allows for complex computations to be executed through carefully designed measurement strategies.
• Evaluate the implications of measurement-based quantum computing for future technological advancements in photonics and information processing.
  • Measurement-based quantum computing holds significant implications for future advancements in both photonics and information processing by leveraging the unique properties of light for computation. Since this model is particularly well-suited for systems utilizing photons, it could lead to new developments in optical communication technologies and secure information transfer methods. The flexibility and adaptability provided by measurement strategies could also pave the way for innovative applications in areas like cryptography and complex problem-solving, reshaping how we think about processing information in a quantum context.

Related terms

Entanglement: A quantum phenomenon where particles become interconnected in such a way that the state of one particle instantaneously influences the state of another, regardless of distance.

Cluster State: A specific type of entangled quantum state used in measurement-based quantum computing, where multiple qubits are entangled in a way that facilitates quantum computations through measurements.

Quantum Gates: Fundamental building blocks of quantum circuits that perform operations on qubits, analogous to classical logic gates, but operate using the principles of quantum mechanics.