Quantum volume definition
Quantum volume refers to a metric used to measure the overall capabilities and error rates of a quantum computer, assessing its computational power. Developed by IBM, it provides a holistic measure of a quantum computer's overall performance, taking into account several factors beyond just the number of qubits. The goal of quantum volume is to provide a more comprehensive benchmark for comparing the power and usefulness of different quantum computers.
See also: Post-quantum cryptography, Puantum error correction
How does quantum volume work?
In classical computing, the basic unit of information is the bit, which can either be a 0 or a 1. These bits are the foundation for all data processing, such as RAM and CPU. Quantum computing introduces a new unit of information — the qubit. Unlike a bit, a qubit can exist in a state of 0, 1, or any quantum superposition of these states. This capability allows quantum computers to process a vast number of possibilities simultaneously.
The calculation of quantum volume involves the following steps:
- 1.Defining a model circuit. The model circuit used has a width and depth equal to the number of qubits, and it involves a sequence of randomly selected gates.
- 2.Running the circuit. This circuit is run on the quantum computer to see if it can successfully handle and execute the operations without significant errors.
- 3.Analyzing and computing the quantum volume. The outputs are compared against the expected results allowing the calculation of the quantum volume.
