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+# Double-bracket quantum algorithms
+
+Qibo features a model implementing double-bracke quantum algorithms (DBQAs) which are helpful for approximating eigenstates based on the ability to run the evolution under the input Hamiltonian.
+
+More specifically, given a Hamiltonian $H_0$, how can we find a circuit which after applying to the reference state (usually $|0\rangle^{\otimes L}$ for $L$ qubits) will approximate an eigenstate?
+
+A standard way is to run variational quantum circuits. For example, Qibo already features  the `VQE` model [2] which provides the implementation of the variational quantum eigensolver framework.
+DBQAs allow to go beyond VQE in that they take a different approach to compiling the quantum circuit approximating the eigenstate.
+
+[1] https://arxiv.org/abs/2206.11772 
+
+[2] https://github.com/qiboteam/vqe-sun