Abstract: A method for simulating a bosonic quantum bit (qubit) on a classical computer are described. The method determines a phase space representation of the qubit in the form of a linear combination of Gaussian functions, each of which is characterized by a mean, a covariance matrix, and a weight coefficient determined from user defined energy parameter and qubit class of the qubit. The qubit may be simulated on a classical computer by applying transformations of quantum logic gates and measurements to update the weight coefficient, mean, and covariance matrix of each of the Gaussian functions.

Abstract: An apparatus includes a plurality of processing layers coupled in series. Each processing layer in the plurality of processing layers includes a Gaussian unit configured to perform a linear transformation on an input signal including a plurality of optical modes. The Gaussian unit includes a network of interconnected beamsplitters and phase shifters and a plurality of squeezers operatively coupled to the network of interconnected beamsplitters and phase shifters. Each processing layer also includes a plurality of nonlinear gates operatively coupled to the Gaussian unit and configured to perform a nonlinear transformation on the plurality of optical modes. The apparatus also includes a controller operatively coupled to the plurality of processing layers and configured to control a setting of the plurality of processing layers.

Abstract: Embodiments described herein provide systems and methods for optimizing a Gaussian representation to design photonic circuits for preparing a given target quantum state. The systems and methods internally consider and optimize quantum representations (e.g., Gaussian transformations, Gaussian and non-Gaussian states). In some embodiments, the systems and methods may produce optimal Gaussian transformations or states. In some embodiments, the systems and methods extract circuit parameters from an optimal Gaussian transformation to produce quantum circuits or designs for generating the optimal states. Embodiments described herein relate to systems and methods for optimizing a Gaussian transformation for state generation.

Abstract: An apparatus includes a plurality of processing layers coupled in series. Each processing layer in the plurality of processing layers includes a Gaussian unit configured to perform a linear transformation on an input signal including a plurality of optical modes. The Gaussian unit includes a network of interconnected beamsplitters and phase shifters and a plurality of squeezers operatively coupled to the network of interconnected beamsplitters and phase shifters. Each processing layer also includes a plurality of nonlinear gates operatively coupled to the Gaussian unit and configured to perform a nonlinear transformation on the plurality of optical modes. The apparatus also includes a controller operatively coupled to the plurality of processing layers and configured to control a setting of the plurality of processing layers.

Abstract: An apparatus includes a plurality of processing layers coupled in series. Each processing layer in the plurality of processing layers includes a Gaussian unit configured to perform a linear transformation on an input signal including a plurality of optical modes. The Gaussian unit includes a network of interconnected beamsplitters and phase shifters and a plurality of squeezers operatively coupled to the network of interconnected beamsplitters and phase shifters. Each processing layer also includes a plurality of nonlinear gates operatively coupled to the Gaussian unit and configured to perform a nonlinear transformation on the plurality of optical modes. The apparatus also includes a controller operatively coupled to the plurality of processing layers and configured to control a setting of the plurality of processing layers.

Abstract: An apparatus includes an optical medium characterized by a third-order nonlinear optical susceptibility. The apparatus also includes a pump light source in optical communication with the optical medium and configured to send a pump light beam to the optical medium. The pump light beam includes a pulsed light beam. The apparatus also includes a drive light source in optical communication with the optical medium and configured to send a drive light beam to the optical medium. The drive light beam includes a continuous wave (CW) light beam. The pump light beam and the drive light beam are configured to generate a signal light beam in a squeezed state of light via spontaneous four-wave mixing in the optical medium.

Abstract: An apparatus includes an optical medium characterized by a third-order nonlinear optical susceptibility. The apparatus also includes a pump light source in optical communication with the optical medium and configured to send a pump light beam to the optical medium. The pump light beam includes a pulsed light beam. The apparatus also includes a drive light source in optical communication with the optical medium and configured to send a drive light beam to the optical medium. The drive light beam includes a continuous wave (CW) light beam. The pump light beam and the drive light beam are configured to generate a signal light beam in a squeezed state of light via spontaneous four-wave mixing in the optical medium.