Exact & formalBell / entanglement
Bell state measurement
A two-qubit entanglement example with a return contract and distribution check.
Explore quantum algorithms and circuits, with resource estimates, verification evidence, and sources.
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The defining behavior was checked exactly: a mathematical identity, a full statevector or stabilizer simulation, or an exhaustive basis-state truth table.
The design was verified by construction plus measured evidence: statistical re-execution, small-instance analytic agreement, sub-block, echo, or invariant checks. Scale-specific bugs can still survive.
The record rests on external authority: peer-reviewed papers, standard textbooks, expert review, or evidence carried over from related verified entries. Nothing here was re-executed by this catalog.
Only automated (LLM-assisted) review or an unreviewed community submission backs this record so far. Treat it as a starting point, not evidence.
A two-qubit entanglement example with a return contract and distribution check.
A bank of disjoint Bell-pair preparations that exposes parallel two-qubit-gate structure.
A fixed all-ones Bernstein–Vazirani instance with the last qubit used as the phase-kickback ancilla.
A deterministic H/S/CNOT brickwork circuit suited to stabilizer and compiler regression checks.
A width-scaled GHZ preparation circuit with one Hadamard and a nearest-neighbor CNOT chain.
A reproducible hardware-efficient VQE layer with parameterized RY rotations and a linear CNOT entangler.
A two-axis variational layer followed by a nearest-neighbor CZ entangling pattern.
A first-order nearest-neighbor ZZ evolution scaffold expressed as CNOT–RZ–CNOT blocks.
A linear graph-state preparation circuit using one Hadamard per qubit and nearest-neighbor CZ edges.
A Hartree–Fock-like computational-basis seed followed by tunable rotations and a CNOT chain.
A deterministic parity-oracle circuit that marks alternating input wires through phase kickback.
A fixed-data feature-map scaffold with Hadamards, local phase rotations, and pairwise ZZ encodings.
A fixed-angle p=1 MaxCut-style QAOA layer on a cycle graph, including cost and mixer blocks.
A cyclic graph-state preparation circuit with Hadamards followed by CZ interactions around a ring.
A forward-and-reverse nearest-neighbor SWAP network for testing routing and qubit-order preservation.
A problem-inspired layer combining ZZ interactions and transverse X rotations for a ring Ising model.
The canonical resource state for one-way (measurement-based) quantum computing: qubits in |+⟩ entangled by CZ along a line.
The symmetric Dicke state |D²₄⟩: a uniform superposition over every 4-qubit basis string with exactly 2 excitations.
A reusable GHZ state preparation circuit with simulator-only evidence.
A graph state built on a 4-cycle rather than an open chain, illustrating how stabilizer generators follow directly from graph adjacency.
The Hadamard-basis (X-basis) states |+⟩ and |−⟩: the eigenstates of the Pauli-X operator, produced from |0⟩/|1⟩ by a single Hadamard gate.
Puts a list of 2ⁿ probabilities into n qubits as amplitudes √p, exactly, with one uniformly controlled RY rotation per qubit.
The three-qubit W state, an equal superposition of every single-excitation basis string that survives the loss of one qubit better than GHZ.
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