Merge pull request #193 from BoxiLi/qrot

Add QROT and MS gate
qutip · Feb 22, 2023 · fd84732 · fd84732
2 parents 5790ddc + bda9f33
commit fd84732
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diff --git a/doc/source/qip-basics.rst b/doc/source/qip-basics.rst
@@ -143,6 +143,7 @@ Gate name                           Description
 "RX"                  Rotation around x axis
 "RY"                  Rotation around y axis
 "RZ"                  Rotation around z axis
+"R"                   Arbitrary single qubit rotation
 "X"                   Pauli-X gate
 "Y"                   Pauli-Y gate
 "Z"                   Pauli-Z gate
@@ -169,6 +170,7 @@ Gate name                           Description
 "ISWAP"               Swap gate with additional phase for 01 and 10 states
 "SQRTSWAP"            Square root of the SWAP gate
 "SQRTISWAP"           Square root of the ISWAP gate
+"MS"                  Mølmer-Sørensen gate
 "FREDKIN"             Fredkin gate
 "TOFFOLI"             Toffoli gate
 "GLOBALPHASE"         Global phase

diff --git a/src/qutip_qip/operations/gateclass.py b/src/qutip_qip/operations/gateclass.py
@@ -29,6 +29,7 @@
     s_gate,
     t_gate,
     cs_gate,
+    qrot,
     qasmu_gate,
     ct_gate,
     cphase,
@@ -62,6 +63,7 @@
     "SQRTNOT",
     "S",
     "T",
+    "R",
     "QASMU",
     "SWAP",
     "ISWAP",
@@ -317,6 +319,8 @@ def get_compact_qobj(self):
             qobj = snot()
         elif self.name == "PHASEGATE":
             qobj = phasegate(self.arg_value)
+        elif self.name == "R":
+            qobj = qrot(*self.arg_value)
         elif self.name == "QASMU":
             qobj = qasmu_gate(self.arg_value)
         elif self.name == "CRX":
@@ -634,6 +638,35 @@ def get_compact_qobj(self):
         return t_gate()
 
 
+class R(SingleQubitGate):
+    r"""
+    Arbitrary single-qubit rotation
+
+    .. math::
+
+        \begin{pmatrix}
+        \cos(\frac{\theta}{2}) & -ie^{-i\phi} \sin(\frac{\theta}{2}) \\
+        -ie^{i\phi} \sin(\frac{\theta}{2}) & \cos(\frac{\theta}{2})
+        \end{pmatrix}
+
+    Examples
+    --------
+    >>> from qutip_qip.operations import R
+    >>> R(0, (np.pi/2, np.pi/2)).get_compact_qobj().tidyup() # doctest: +NORMALIZE_WHITESPACE
+    Quantum object: dims = [[2], [2]], shape = (2, 2), type = oper, isherm = False
+    Qobj data =
+    [[ 0.70711 -0.70711]
+     [ 0.70711  0.70711]]
+    """
+
+    def __init__(self, targets, arg_value=None, **kwargs):
+        super().__init__(targets=targets, arg_value=arg_value, **kwargs)
+        self.latex_str = r"{\rm R}"
+
+    def get_compact_qobj(self):
+        return qrot(*self.arg_value)
+
+
 class QASMU(SingleQubitGate):
     r"""
     QASMU gate.
@@ -1140,6 +1173,7 @@ def get_compact_qobj(self):
     "SQRTNOT": SQRTNOT,
     "S": S,
     "T": T,
+    "R": R,
     "QASMU": QASMU,
     "SWAP": SWAP,
     "ISWAP": ISWAP,

diff --git a/tests/test_gates.py b/tests/test_gates.py
@@ -10,7 +10,7 @@
 from qutip_qip.operations import (
     X, Y, Z, RX, RY, RZ, H, SQRTNOT, S, T, QASMU, CNOT, CPHASE, ISWAP, SWAP,
     CZ, SQRTSWAP, SQRTISWAP, SWAPALPHA, SWAPALPHA, MS, TOFFOLI, FREDKIN,
-    BERKELEY, expand_operator)
+    BERKELEY, R, expand_operator)
 
 
 def _permutation_id(permutation):
@@ -355,6 +355,7 @@ def test_gates_class():
     circuit1.add_gate("SQRTNOT", 0)
     circuit1.add_gate("S", 2)
     circuit1.add_gate("T", 1)
+    circuit1.add_gate("R", 1, arg_value=(np.pi/4, np.pi/6))
     circuit1.add_gate("QASMU", 0, arg_value=(np.pi/4, np.pi/4, np.pi/4))
     circuit1.add_gate("CNOT", controls=0, targets=1)
     circuit1.add_gate("CPHASE", controls=0, targets=1, arg_value=np.pi/4)
@@ -381,6 +382,7 @@ def test_gates_class():
     circuit2.add_gate(SQRTNOT(0))
     circuit2.add_gate(S(2))
     circuit2.add_gate(T(1))
+    circuit2.add_gate(R(1, (np.pi/4, np.pi/6)))
     circuit2.add_gate(QASMU(0, (np.pi/4, np.pi/4, np.pi/4)))
     circuit2.add_gate(CNOT(0, 1))
     circuit2.add_gate(CPHASE(0, 1, np.pi/4))