A device that takes data as input and does some sort of operations on that data with a process that can only be described using quantum physics.
What is a Quantum Computer?
Method to create a diagram of the quantum circuit.
What is qc.draw() ?
This gate flips the |0> state to |1> and vice versa. equivalent to RX gate for the angle π, or to “HZH”. Bit flip.
What is the X gate or NOT gate?
Statement that will create a quantum circuit with four quantum bits and four classical bits.
What is QuantumCircuit(4, 4)?
This simulator allows ideal and noisy multi-shot execution of qiskit circuits and returns counts or memory. It also allows for measurements, reset, conditionals.
What is the qasm_simulator?
A weighted sum, or linear combination, of two or more quantum states.
What is Superposition?
Visualization for plotting any single qubit state on the surface of a sphere.
What is a Bloch Sphere?
This gate is equivalent to RY gate for the angle π (pi). Equivalent to applying X and Z, up to a global phase factor. Bit flip and phase flip.
What is the Y gate?
This method tells you the critical path, the longest path between data input and output. It's a measure of how many "layers" of quantum gates, executed in parallel, it takes to complete the computation defined by the circuit.
What is .depth()?
This simulator allows for ideal single-shot execution of qiskit circuits and returns the final statevector of the simulator after application. It also Allows for measurements, reset, conditionals.
What is the statevector_simulator?
A property of quantum systems comprised of more than one subsystems (i.e. qubits), where the quantum state of any one subsystem cannot be uniquely described independently of the remaining subsystems.
What is Entanglement?
Qiskit uses ordering that is different than most physics textbooks. It orders the n-th qubit on this side.
What is the left side?
E.g. If qubit 0 is in state 0, qubit 1 is in state 0, and qubit 2 is in state 1, Qiskit would represent this state as |100>.
This gate acts as an identity gate on the |0> state and multiplies the sign of the |1> state by -1. It therefore flips the |+> and |-> states. Phase flip.
What is the Z gate?
Method used to combine circuits with different number of qubits.
What is .compose()?
This simulator allows for ideal single-shot execution of qiskit circuits and returns final unitary matrix of the circuit itself. It allows only gates. The circuit cannot contain measure or reset operations for this backend.
What is the unitary_simulator?
A reversible (unitary) operation applied to one or more qubits.
What is a Quantum Gate?
Used as a visual tool. Also an instruction to the transpiler to stop it from cancelling out gates or collapsing gates into a single operation. Does not add to depth.
What is a Barrier?
This gate rotates the states |0> and |1> to |+> and |-> respectively. It is useful for making superpositions.
What is the H gate or Hadamard?
A method to convert a quantum circuit to QASM.
What is .to_qasm() or .qasm()?
A module of Python-based quantum simulators. This module is an older version of Aer (the larger and fancier simulation package).
What is BasicAer?
A collection of qubits on which gates and other operations act.
What is a Quantum Register?
A plot method that can visualise entangled states.
What is plot_state_qsphere()?
This gate is equivalent to RZ gate for the angle π/4.
What is the T gate?
A method to convert from QASM.
What is .from_qasm_str() or .from_qasm_file()?
This method shows versions of all that packages and is the recommended method to use.
What is "qiskit.__qiskit_version__"?
NOT "qiskit.__version__" - this shows only the version of the terra package.