Add ECR gate

bqskit/ir/gates/constant/__init__.py

@@ -14,6 +14,7 @@
 from bqskit.ir.gates.constant.cx import CXGate
 from bqskit.ir.gates.constant.cy import CYGate
 from bqskit.ir.gates.constant.cz import CZGate
+from bqskit.ir.gates.constant.ecr import ECRGate
 from bqskit.ir.gates.constant.h import HGate
 from bqskit.ir.gates.constant.identity import IdentityGate
 from bqskit.ir.gates.constant.iswap import ISwapGate
@@ -57,6 +58,7 @@
     'CXGate',
     'CYGate',
     'CZGate',
+    'ECRGate',
     'HGate',
     'IdentityGate',
     'ISwapGate',

bqskit/ir/gates/constant/ecr.py

@@ -0,0 +1,26 @@
+"""This module implements the ECRGate."""
+from bqskit.ir.gates.qubitgate import QubitGate
+from bqskit.ir.gates.constantgate import ConstantGate
+from bqskit.qis.unitary.unitarymatrix import UnitaryMatrix
+import math
+
+class ECRGate(ConstantGate, QubitGate):
+    _name = 'ecr'
+    _num_qudits = 2
+    _qasm_name = 'ecr'
+    _utry = UnitaryMatrix([
+            [0, 0, 1*1/math.sqrt(2), 1j*1/math.sqrt(2)],
+            [0, 0, 1j*1/math.sqrt(2), 1*1/math.sqrt(2)],
+            [1*1/math.sqrt(2), -1j*1/math.sqrt(2), 0, 0],
+            [-1j*1/math.sqrt(2), 1*1/math.sqrt(2), 0, 0]
+        ])
+
+    def __init__(self) -> None:
+        pass 
+
+    def get_qasm_gate_def(self) -> str:
+        qasm_rzx = "gate rzx(param0) q0,q1 { h q1; cx q0,q1; rz(param0) q1; cx q0,q1; h q1; }"
+        qasm_ecr = "gate ecr q0,q1 { rzx(pi/4) q0,q1; x q0; rzx(-pi/4) q0,q1; }"
+        return qasm_rzx +"\n" + qasm_ecr
+
+