glossary

Download Python script

Download Notebook

View on GitHub

# Glossary¶

Expressions that are grouped together are used synonymously in the Strawberry Fields documentation.

- backend
- Executes quantum programs. Can be either a classical simulator or a
quantum hardware device, local or remote. Different backends can have different capabilities
in terms of efficiency and which class of circuits they can execute.
See:
`BaseBackend`

- circuit
- quantum circuit
- program
- A sequence of quantum operations acting on a quantum register.
Typically contains measurements that produce a stochastic classical output.
Represents a quantum computation.
See:
`Program`

- circuit class
- circuit family
- A well-defined subset of quantum circuits.
Members of a given circuit class can potentially be evaluated
on more than one backend, and each backend has an associated circuit class it
can execute.
See:
`CircuitSpecs`

- compilation
- The process of converting a source quantum program into an equivalent program that belongs in the target circuit class. The compilation can fail if the program cannot be made equivalent to the target circuit class.
- equivalent circuit
- equivalent program
- Two quantum circuits are equivalent iff they produce the same output probability distributions. Two equivalent circuits are not necessarily in the same circuit class.
- engine
- A class for executing quantum programs on a specific backend.
See:
`BaseEngine`

- frontend
- All components of Strawberry Fields that are user-facing. Includes the user interface
(engine, program, operation);
excludes the backends.
See:
`BaseEngine`

,`Program`

,`Operation`

- gate
- quantum gate
- A quantum operation that changes the state of the register. Analogous to a logic gate in a Boolean circuit.
- measurement
- A quantum operation that returns classical information.
- operation
- quantum operation
- Something that acts on specific subsystems of the register, changing its state and
possibly returning classical information, e.g., a state preparation, gate,
measurement, etc.
See:
`Operation`

- register
- quantum register
- system
- mode
- qumode
- A quantum system (or a simulation of one) storing the state of the quantum computation. Typically consists of several subsystems (which in CV quantum computing are called modes).
- state preparation
- preparation
- An operation where a quantum system or subsystem is prepared in a known fixed state. Typically accomplished by applying a specific sequence of gates to a known reference state.