Merge branch 'qrom_demo_2' of https://github.com/PennyLaneAI/qml into…

… qrom_demo_2

Makefile

@@ -73,10 +73,11 @@ environment:
  if [ '$(UPGRADE_PL)' = 'true' ]; then\
  echo "Updating PennyLane and plugins to latest ... ";\
  PYTHON_VENV_PATH=`$(POETRY_BIN) env info --path`;\
- $$PYTHON_VENV_PATH/bin/python -m pip install --upgrade git+https://github.com/PennyLaneAI/pennylane.git#egg=pennylane;\
+ $$PYTHON_VENV_PATH/bin/python -m pip install --upgrade git+https://github.com/PennyLaneAI/pennylane.git@v0.37.0-rc0#egg=pennylane;\
  $$PYTHON_VENV_PATH/bin/python -m pip install --upgrade git+https://github.com/PennyLaneAI/pennylane-cirq.git#egg=pennylane-cirq;\
  $$PYTHON_VENV_PATH/bin/python -m pip install --upgrade git+https://github.com/PennyLaneAI/pennylane-qiskit.git#egg=pennylane-qiskit;\
  $$PYTHON_VENV_PATH/bin/python -m pip install --upgrade git+https://github.com/PennyLaneAI/pennylane-qulacs.git#egg=pennylane-qulacs;\
  $$PYTHON_VENV_PATH/bin/python -m pip install -i https://test.pypi.org/simple/ PennyLane-Lightning --pre --upgrade;\
+ $$PYTHON_VENV_PATH/bin/python -m pip install -i https://test.pypi.org/simple/ PennyLane-Catalyst==0.7.0.dev0 --upgrade;\
  fi;\
  fi

_static/authors/dan_strano.txt

@@ -0,0 +1,4 @@
+.. bio:: Dan Strano
+ :photo: ../_static/authors/dan_strano.jpg
+
+ Dan Strano is a technical staff member at `Unitary Fund <https://unitary.fund>`__. Additionally, he has been the lead author of the Qrack simulator framework since 2017.

demonstrations/tutorial_qchem_external.metadata.json

@@ -6,7 +6,7 @@
  }
  ],
  "dateOfPublication": "2023-01-03T00:00:00+00:00",
- "dateOfLastModification": "2024-01-01T00:00:00+00:00",
+ "dateOfLastModification": "2024-06-20T00:00:00+00:00",
  "categories": [
  "Quantum Chemistry", "Devices and Performance"
  ],

demonstrations/tutorial_qchem_external.py

@@ -180,6 +180,31 @@
 ##############################################################################
 # You can verify that this state is a superposition of the Hartree-Fock state and a doubly-excited
 # state.
+#
+# Converting fermionic operators
+# ------------------------------
+# Fermionic operators are commonly used to construct observables for molecules and spin systems.
+# You can easily convert between fermionic operators created with PennyLane and OpenFermion by using
+# the :func:`~.pennylane.from_openfermion` and :func:`~.pennylane.to_openfermion` functions. Let's
+# look at some examples. First, we create a fermionic operator with OpenFermion and convert it to a
+# PennyLane fermionic operator.
+
+from openfermion import FermionOperator
+openfermion_op = 0.5 * FermionOperator('0^ 2') + FermionOperator('0 2^')
+pennylane_op = qml.from_openfermion(openfermion_op)
+print(pennylane_op)
+
+##############################################################################
+# The resulting operator can be used in PennyLane like any other fermionic object. We now take this
+# PennyLane fermionic operator and convert it back to an OpenFermion operator.
+
+openfermion_op = qml.to_openfermion(pennylane_op)
+print(openfermion_op)
+
+##############################################################################
+# The :func:`~.pennylane.from_openfermion` and :func:`~.pennylane.to_openfermion` functions support
+# converting several operator types. You can look at the function documentations for more details
+# and examples.
 
 ##############################################################################
 # Conclusions
@@ -195,8 +220,8 @@
 # function.
 # 2. We can directly use one- and two-electron integrals from PySCF, but we need to convert the
 # tensor containing the two-electron integrals from chemists' notation to physicists' notation.
-# 3. We can easily convert OpenFermion operators to PennyLane operators using the
-# :func:`~.pennylane.import_operator` function.
+# 3. We can easily convert between OpenFermion operators and PennyLane operators using the
+# :func:`~.pennylane.from_openfermion` and :func:`~.pennylane.to_openfermion` functions.
 # 4. Finally, we can convert PySCF wave functions to PennyLane state vectors using the
 # :func:`~.pennylane.qchem.import_state` function.
 #