GMS¶

class
GMS
(num_qubits, theta)[source]¶ Bases:
qiskit.circuit.quantumcircuit.QuantumCircuit
Global Mølmer–Sørensen gate.
Circuit symbol:
┌───────────┐ q_0: ┤0 ├ │ │ q_1: ┤1 GMS ├ │ │ q_2: ┤2 ├ └───────────┘
Expanded Circuit:
The Mølmer–Sørensen gate is native to iontrap systems. The global MS can be applied to multiple ions to entangle multiple qubits simultaneously [1].
In the twoqubit case, this is equivalent to an XX(theta) interaction, and is thus reduced to the RXXGate. The global MS gate is a sum of XX interactions on all pairs [2].
\[GMS(\chi_{12}, \chi_{13}, ..., \chi_{n1 n}) = exp(i \sum_{i=1}^{n} \sum_{j=i+1}^{n} X{\otimes}X \frac{\chi_{ij}}{2})\]References:
[1] Sørensen, A. and Mølmer, K., Multiparticle entanglement of hot trapped ions. Physical Review Letters. 82 (9): 1835–1838. arXiv:9810040
[2] Maslov, D. and Nam, Y., Use of global interactions in efficient quantum circuit constructions. New Journal of Physics, 20(3), p.033018. arXiv:1707.06356
Create a new Global Mølmer–Sørensen (GMS) gate.
 Parameters
num_qubits (
int
) – width of gate.theta (
Union
[List
[List
[float
]],ndarray
]) – a num_qubits x num_qubits symmetric matrix of interaction angles for each qubit pair. The upper triangle is considered.
Attributes

ancillas
¶ Returns a list of ancilla bits in the order that the registers were added.

calibrations
¶ Return calibration dictionary.
 The custom pulse definition of a given gate is of the form
{‘gate_name’: {(qubits, params): schedule}}

clbits
¶ Returns a list of classical bits in the order that the registers were added.

data
¶ Return the circuit data (instructions and context).
 Returns
a listlike object containing the tuples for the circuit’s data.
Each tuple is in the format
(instruction, qargs, cargs)
, where instruction is an Instruction (or subclass) object, qargs is a list of Qubit objects, and cargs is a list of Clbit objects. Return type
QuantumCircuitData

extension_lib
= 'include "qelib1.inc";'¶

global_phase
¶ Return the global phase of the circuit in radians.

header
= 'OPENQASM 2.0;'¶

instances
= 16¶

metadata
¶ The user provided metadata associated with the circuit
The metadata for the circuit is a user provided
dict
of metadata for the circuit. It will not be used to influence the execution or operation of the circuit, but it is expected to be passed between all transforms of the circuit (ie transpilation) and that providers will associate any circuit metadata with the results it returns from execution of that circuit.

num_ancillas
¶ Return the number of ancilla qubits.

num_clbits
¶ Return number of classical bits.

num_parameters
¶ Convenience function to get the number of parameter objects in the circuit.

num_qubits
¶ Return number of qubits.

parameters
¶ Convenience function to get the parameters defined in the parameter table.

prefix
= 'circuit'¶

qubits
¶ Returns a list of quantum bits in the order that the registers were added.