Entanglement bounds on the performance of quantum computing architectures.

Area of Science:

• Quantum computing
• Quantum information science
• Computer architecture

Background:

• Designing quantum computers involves selecting qubit connectivity architectures.
• Evaluating the performance of quantum architecture connectivity graphs is challenging.
• Entangled states are crucial for quantum computation.

Purpose of the Study:

• To introduce a new metric, the isoperimetric number, for evaluating quantum computer architectures.
• To establish a lower bound on the time required for creating highly entangled states using this metric.
• To assess the viability of a hierarchical qubit architecture compared to traditional ones.

Main Methods:

• Defining a resource metric based on two-qubit unitary operations.
• Allowing for rapid measurements and classical feedback in the resource model.
• Applying the isoperimetric number to analyze qubit connectivity graphs.
• Developing a constructive protocol to saturate the derived lower bound.

Main Results:

• The isoperimetric number provides a lower bound on the time to create highly entangled states.
• A hierarchical qubit architecture is identified as a promising alternative to grid architectures.
• The established lower bound can be achieved with a constructive protocol, up to logarithmic factors.

Conclusions:

• The isoperimetric number is a valuable tool for assessing quantum computer architectures.
• Hierarchical architectures offer potential advantages for quantum computation.
• The developed protocol demonstrates the practical achievability of entanglement creation bounds.