Abstract: Some embodiments in the present disclosure relate to an apparatus and methods to excite a trapped ion. A first laser beam and a second laser beam pass through at least one common lens of an objective. The two laser beams are focused by said objective at the position of the trapped ion. A moving standing wave is generated at the position of the trapped ion, which induces a force on the trapped ion. Two ions may be entangled by generating such moving standing wave at the respective positions of both of said ions.

Abstract: An apparatus includes an optical circuit having at least one reconfigurable beamsplitter and is configured to receive a plurality of input optical modes in a Gaussian state and generate a plurality of output optical modes. The apparatus also includes at least one detector optically coupled with the optical circuit and configured to perform a non-Gaussian measurement of a first output optical mode from the plurality of output optical modes. The non-Gaussian measurement of the first output optical mode is configured to cause a second output optical mode from the plurality of output optical modes to be in a first non-Gaussian state. The apparatus also includes a controller operatively coupled to the optical circuit and configured to change a setting of the at least one reconfigurable beamsplitter to cause the second output optical mode from the plurality of output optical modes to be in a second non-Gaussian state.

Abstract: A scalar magnetometer includes a sensor element, a circuit carrier, a pump radiation source, a radiation receiver and evaluation means. The pump radiation source emits pump radiation. The sensor element preferably includes one or more NV centers in diamond as paramagnetic centers. This paramagnetic center emits fluorescence radiation when irradiated with pump radiation. The radiation receiver converts a intensity signal of the fluorescence radiation into a receiver output signal. The evaluation means detects and/or stores and/or transmits the value of the receiver output signal. The material of the circuit carrier is preferably transparent for the pump radiation in the radiation path between pump radiation source and sensor element and transparent for the fluorescence radiation in the radiation path between sensor element and radiation receiver. The components sensor element, pump radiation source, radiation receiver and evaluation means are preferably mechanically attached to the circuit carrier .

Abstract: A system for scalable, fault-tolerant photonic quantum computing includes multiple optical circuits, multiple photon number resolving detectors (PNRs), a multiplexer, and an integrated circuit (IC). During operation, the optical circuits generate output states via Gaussian Boson sampling (GBS), and the PNRs generate qubit clusters based on the output states. The multiplexer multiplexes the qubit clusters and replaces empty modes with squeezed vacuum states, to generate multiple hybrid resource states. The IC stitches together the hybrid resource states into a higher-dimensional cluster state that includes states for fault-tolerant quantum computation.

Abstract: A method includes receiving a representation of an N-mode interferometer and a representation of at least one imperfection associated with the N-mode interferometer at a processor, N being a positive integer value. The processor identifies multiple two-mode interferometers and multiple phases based on the representation of the N-mode interferometer and the representation of the at least one imperfection. The multiple two-mode interferometers and the multiple phases are configured to apply a unitary transformation to an input signal. The method also includes sending a signal to cause at least one of storage or display of a representation of the multiple two-mode interferometers and a representation of the multiple phases.

Abstract: Protected quantum dots are protected from degradation, particularly in aqueous environments, The system comprises quantum dots, hydrophobic core, and hydrophilic shell. The quantum dots are entrapped in and protected by the hydrophobic core. The core polymer is covalently bonded to a hydrophilic shell polymer or protein. Quantum yield is better maintained than for non-encapsulated quantum dots in an aqueous environment. Optionally, ligands are attached to the hydrophilic shell to target delivery of the protected quantum dots, In an alternative embodiment, quantum dots are entrapped in the hydrophilic shell, or in both the shell and the core.

Abstract: An apparatus includes a light source to provide a plurality of input optical modes in a squeezed state. The apparatus also includes a network of interconnected reconfigurable beam splitters (RBSs) configured to perform a unitary transformation of the plurality of input optical modes to generate a plurality of output optical modes. An array of photon counting detectors is in optical communication with the network of interconnected RBSs and configured to measure the number of photons in each mode of the plurality of the output optical modes after the unitary transformation. The apparatus also includes a controller operatively coupled to the light source and the network of interconnected RBSs. The controller is configured to control at least one of the squeezing factor of the squeezed state of light, the angle of the unitary transformation, or the phase of the unitary transformation.

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 light source to provide a plurality of input optical modes in a squeezed state. The apparatus also includes a network of interconnected reconfigurable beam splitters (RBSs) configured to perform a unitary transformation of the plurality of input optical modes to generate a plurality of output optical modes. An array of photon counting detectors is in optical communication with the network of interconnected RBSs and configured to measure the number of photons in each mode of the plurality of the output optical modes after the unitary transformation. The apparatus also includes a controller operatively coupled to the light source and the network of interconnected RBSs. The controller is configured to control at least one of the squeezing factor of the squeezed state of light, the angle of the unitary transformation, or the phase of the unitary transformation.

Abstract: A quantum chemistry method includes causing display, via a processor, of a representation of a plurality of controlled single-excitation quantum gates. A selection of a subset of controlled single-excitation quantum gates from the plurality of controlled single-excitation quantum gates is received at the processor. A particle-preserving unitary for a quantum chemistry simulation is identified based on the selected subset of controlled single-excitation quantum gates. At least one controlled single-excitation quantum gate from the plurality of controlled single-excitation quantum gates can be configured to apply a Givens rotation.

Abstract: A method includes causing activation, at a first time, of a first set of squeezed light sources from a plurality of squeezed light sources of a Gaussian boson sampling (GBS) circuit. At a second time after the first time, a first photon statistic is detected at a first output port from a plurality of output ports of the GBS circuit. At a third time after the first time, a second set of squeezed light sources from the plurality of squeezed light sources of the GBS circuit is activated, the second set of squeezed light sources being different from the first set of squeezed light sources. At a fourth time after the third time, a second photon statistic is detected at a second output port from the plurality of output ports of the GBS circuit. At least one transformation matrix is estimated that represents a linear optical interferometer of the GBS circuit based on the first photon statistic and the second photon statistic.

Abstract: A method of measuring a physical quantity implemented in a hybrid classical-quantum system, the method comprising initializing the plurality of controllable quantum systems in an initial state, applying a set of preparation gates to the plurality of controllable quantum systems for preparing the plurality of controllable quantum systems in a non-classical state, evolving the non-classical state over a time period for obtaining an evolved state of the plurality of controllable quantum systems, applying a set of decoding gates to the plurality of controllable quantum systems in the evolved state, performing a measurement of the plurality of controllable quantum systems, and determining a derived value of the physical quantity based on a mapping function between an outcome of the measurement and the physical quantity on the classical computation system.

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: A method includes configuring a first plurality of beamsplitters in a network of interconnected beamsplitters of an optical circuit into a transmissive state. The optical circuit is configured to perform a linear transformation of N input optical modes, where N is a positive integer. The first plurality of beamsplitters is located along a beam path within the optical circuit and traversing a target location. The method also includes configuring a second plurality of beamsplitters in the network of interconnected beamsplitters of the optical circuit into a reflective state to reconfigure the optical circuit into a reconfigured optical circuit. The reconfigured optical circuit is configured to perform a linear transformation on M input optical modes, where M is a positive integer less than N. The second plurality of beamsplitters is located along at least one edge of the optical circuit.

Abstract: An apparatus includes a plurality of interconnected reconfigurable beam splitters and a plurality of phase shifters collectively configured to define a network of optical devices. The network of optical devices is configured to perform a universal transformation on a plurality of input optical signals via a triangular architecture. The apparatus also includes a first delay line optically coupled to the network of optical devices and configured to send at least one output optical signal from a plurality of output optical signals of the network of optical devices to interact with at least one input optical signal in the plurality of input optical signals within the network of optical devices.

Abstract: A method for forming a sensing system responsive to a wavefield of acoustic or seismic signals. One embodiment includes providing a foil layer having first and second opposing surfaces and piezoelectric properties. The foil layer, configured as a sheet, is positioned about a frame surface which provides the foil layer a stable shape while permitting the sheet configuration of the foil layer to be responsive to a wavefield of seismic or acoustic energy. Coupling between the foil layer and the frame is so limited as to render direct coupling of the foil layer with signals of the wavefield the predominant means for stimulating the sensor element with seismic energy.

Abstract: A device for generating and controlling a magnetic field strength and a method for generating and controlling a magnetic field strength are disclosed. The generation is very stable and precise. Preferably, reference values of physical variable can be generated relatively simply and economically. In addition, magnetic flux densities can be measured with high resolution and, in particular, highly robustly. The device and the method can also be used for transmitting information, in particular for ultra-wide band communication. The required devices can be very small, in particular miniature, and mobile.

Abstract: A method includes receiving a representation of an N-mode interferometer and a representation of at least one imperfection associated with the N-mode interferometer at a processor, N being a positive integer value. The processor identifies multiple two-mode interferometers and multiple phases based on the representation of the N-mode interferometer and the representation of the at least one imperfection. The multiple two-mode interferometers and the multiple phases are configured to apply a unitary transformation to an input signal. The method also includes sending a signal to cause at least one of storage or display of a representation of the multiple two-mode interferometers and a representation of the multiple phases.

Abstract: A system for scalable, fault-tolerant photonic quantum computing includes multiple optical circuits, multiple photon number resolving detectors (PNRs), a multiplexer, and an integrated circuit (IC). During operation, the optical circuits generate output states via Gaussian Boson sampling (GBS), and the PNRs generate qubit clusters based on the output states. The multiplexer multiplexes the qubit clusters and replaces empty modes with squeezed vacuum states, to generate multiple hybrid resource states. The IC stitches together the hybrid resource states into a higher-dimensional cluster state that includes states for fault-tolerant quantum computation.

Abstract: A system for scalable, fault-tolerant photonic quantum computing includes multiple optical circuits, multiple photon number resolving detectors (PNRs), a multiplexer, and an integrated circuit (IC). During operation, the optical circuits generate output states via Gaussian Boson sampling (GBS), and the PNRs generate qubit clusters based on the output states. The multiplexer multiplexes the qubit clusters and replaces empty modes with squeezed vacuum states, to generate multiple hybrid resource states. The IC stitches together the hybrid resource states into a higher-dimensional cluster state that includes states for fault-tolerant quantum computation.