We study the quantum circuit complexity of cosmological perturbations in different models early universe. A natural measure for is based on symplectic group, allowing us to identify with geodesics hyperbolic plane. investigate both mode functions and physical perturbations, arguing that latter often provides a more insightful description physics involved. In all total reached rather large. Infl...

A logic for reasoning about quantum circuits and protocols is proposed. It incorporates the basic features of quantum theoryprobability, unitary dynamics, tensor products and measurement. The underlying language could be used for verification and synthesis of quantum circuits. Important algorithms like the quantum search algorithm of Grover are discussed. The logic also forms the foundation on ...

V 3 Si thin films are known to be superconducting with transition temperatures up 15 K, depending on the annealing temperature and properties of substrate underneath. Here we investigate film structural prospect further integration in silicon technology for quantum circuits. Two challenges have been identified: (i) large difference thermal expansion coefficient between leads strains after proce...

Probabilistic graphical models such as Bayesian networks are widely used to model stochastic systems perform various types of analysis probabilistic prediction, risk analysis, and system health monitoring, which can become computationally expensive in large-scale systems. While demonstrations true quantum supremacy remain rare, computing applications managing exploit the advantages amplitude am...

We have designed and operated a superconducting tunnel junction circuit that behaves as a two-level atom: the "quantronium." An arbitrary evolution of its quantum state can be programmed with a series of microwave pulses, and a projective measurement of the state can be performed by a pulsed readout subcircuit. The measured quality factor of quantum coherence Qphi approximately 25,000 is suffic...