Imperfect Entangling Power of Quantum Gates

Abstract

Achieving perfect control over the parameters defining a quantum gate is, in general, a very challenging task, and at the same time, environmental interactions can introduce disturbances to the initial states as well. Here we address the problem of how the imperfections in unitaries and noise present in the input states affect the entanglement-generating power of a given quantum gate -- we refer to it as imperfect (noisy) entangling power. We observe that, when the parameters of a given unitary are chosen randomly from a Gaussian distribution centered around the desired mean, the quenched average entangling power -- averaged across multiple random samplings -- exhibits intriguing behavior like it may increase or show nonmonotonic behavior with the increase of disorder strength for certain classes of diagonal unitary operators. For arbitrary unitary operators, the quenched average power tends to stabilize, showing almost constant behavior with variation in the parameters instead of oscillating. Our observations also reveal that, in the presence of a local noise model, the input states that maximize the entangling power of a given unitary operator differ considerably from the noiseless scenario. Additionally, we report that the rankings among unitary operators according to their entangling power in the noiseless case change depending on the noise model and noise strength.

17 pages, 16 figures

References in corpus (44)

• Quantum entanglement
• Separability Criterion for Density Matrices
• Elementary gates for quantum computation
• Separability of Mixed States: Necessary and Sufficient Conditions
• Distributed Entanglement
• Persistent entanglement in arrays of interacting particles
• Quantum Coherence as a Resource
• The classical-quantum boundary for correlations: discord and related measures
• Multi-photon entanglement and interferometry
• Quantum computing with trapped ions
• Measurement-based quantum computation
• Open Quantum Systems. An Introduction
• General Monogamy Inequality for Bipartite Qubit Entanglement
• A simple formula for the average gate fidelity of a quantum dynamical operation
• Quantum Error Mitigation
• Sudden transition between classical and quantum decoherence
• Optimal Quantum Circuits for General Two-Qubit Gates
• Optimal Creation of Entanglement Using a Two--Qubit Gate
• On the Entangling Power of Quantum Evolutions
• A geometric theory of non-local two-qubit operations
• Entanglement of Quantum Evolutions
• Monogamy Inequality in terms of Negativity for Three-Qubit States
• Quantum discord and its allies: a review
• Entanglement capabilities of non-local Hamiltonians
• Comparative investigation of the freezing phenomena for quantum correlations under nondissipative decoherence
• Channel Capacities versus Entanglement Measures in Multiparty Quantum States
• Hierarchies of Geometric Entanglement
• Interaction cost of non-local gates
• Optimal Entanglement Generation from Quantum Operations
• Quantum entanglement of unitary operators on bi-partite systems
• Universal qudit gate synthesis for transmons
• Performing SU($d$) operations and rudimentary algorithms in a superconducting transmon qudit for $d=3$ and $d=4$
• Entangling Power of Permutations
• Entangling power and local invariants of two-qubit gates
• To freeze or not to: Quantum correlations under local decoherence
• Robust asymptotic entanglement under multipartite collective dephasing
• Discording power of quantum evolutions
• Characterizing the geometrical edges of nonlocal two-qubit gates
• Classical Spin Models with Broken Continuous Symmetry: Random Field Induced Order and Persistence of Spontaneous Magnetization
• Classical spin models with broken symmetry: Random Field Induced Order and Persistence of spontaneous magnetization in presence of a random field
• Entangling power of multipartite unitary gates
• Scale-invariant freezing of entanglement
• Entangling power of two-qubit gates on mixed states
• Production of genuine multimode entanglement in circular waveguides with long-range interactions