Second Foundation

Turing Inc.

Michele Reilly

Jonathan Alexander Lee

Simon Devitt

A multiplexed single photon source for quasi-deterministically generating single photons, wherein heralded random single photons generated by pulsed random single photon source are sent through a series of optical switches each having first and second input and output modes and each capable of being switched from a first state corresponding to a SWAP operation to a second state corresponding to an Identity operation on the mode space, whereby the first and second input and output modes of the switches are connected in series to form a first and second optical path respectively, and whereby a first output mode of a last optical switch forms the output mode of the multiplexed single photon source and a second output mode of the last optical switch is connected by a delay loop introducing a time delay Tto the second input mode of a first optical switch. It furthermore relates to a method of quasi-deterministically generating single photons with such a multiplexed single photon source, the method comprising initializing, before or at the start of a first cycle, the first switch in the first state and all subsequent switches in the second state; switching, when the generation of a random single photon is heralded, the first switch to the second state after that photon has been routed onto the closed optical path formed by the second optical path and the delay loop, thereby ensuring that the photon may loop around the closed optical path; and, switching, at the start of the Nth cycle, a last switch of the series of optical switches into the first state, thereby causing the photon to be routed out of the closed optical path and into the output mode of the multiplexed single photon source, such that the photon is output quasi-deterministically at a time N Td after the start of the first cycle.

Multiplexed single photon source using one-way switching elements

Described herein are systems and methods for coupling Nitrogen Vacancy (NV)-defects in a quantum computing architecture. A diamond wafer comprises separated implantation sites, at least a portion of which comprise a single NV-defect. An optical cavity system comprises cavity sites aligned to the implantation sites. An integrated optics system includes a first chip module comprising optical waveguides and associated switchable elements, photon sources, photon detectors, and fiber optic connections. A first switchable element couples a first pair of NV-defects by splitting a beam emitted by a photon source, via a first optical waveguide, to the cavity sites aligned to the implantation sites of the first pair of NV-defects. A second switchable element couples a second pair of NV-defects by splitting a beam emitted by a photon source, via a second optical waveguide, to the cavity sites aligned to the implantation sites of the second pair of NV-defects.

Optically coupled nitrogen vacancy-defect system for scalable qubit arrays

Described is a method of setting up a plurality of quantum communications links, forming a quantum network providing provably secure communications and internet services over intercontinental distances without requiring direct line of sight communication or the intermediate use of the entanglement resource of satellites. Also described is a quantum communicator device for use in this method. Two or more quantum memory units are disposed at a first location, an entangled link is set up between at least two of the quantum memory units, at least one of the quantum memory units sharing in the entangled link is physically transported to a second location. The quantum communicator device comprises communications nodes, an optical interface to set up entanglement to other devices and storage nodes, each node in the form of a quantum memory unit capable of storing quantum information for a desired length of time, i.e. weeks or longer.

Method and device for setting up long range quantum communications networks

Described herein are methods and systems for controlling an integrated optics control system for quantum computing using a quantum bios chip. A quantum bios chip, comprising one or more qubit connection geometries and one or more error correction codes associated with the qubit connection geometries, receives instructions associated with a quantum computing application. The quantum bios chip configures one or more switching elements of an integrated optics control system coupled to the quantum bios chip, the switching elements controlling entanglement of one or more qubits of a quantum computer and the switching elements configured based upon a selected one of the one or more qubit connection geometries and one of the one or more error correction codes that is compatible with the selected one of the one or more qubit connection geometries.

Quantum bios for reconfiguring quantum computing architectures

Described herein is a Quantum Computing device comprising a first and a second square patch of qubits, each of the first and second square patch of qubits representing a logical qubit and being in a joint quantum state corresponding to a surface code, the surface code having a distance of two or more. The first and second square patch of qubits have a side-length equal to the distance plus one qubits. The device furthermore comprises one or more chain of qubits prepared in a joint GHZ state serving as a data bus. The chain of qubits neighbors both the first and the second square patch of qubits and has a length equal to or greater than the sum of the two side-lengths.

Topological quantum error correction using a data bus

A system for locating errors for quantum computing includes an interface, a shift array, a comparison block, a tree pipeline, and a serializer. The interface is configured to receive a set of quantum bit values, wherein the set of quantum bit values comprise a subset of quantum bit values in a quantum bit array. The shift array is configured to store a prior set of quantum bit values read from identical quantum bit locations at a prior time corresponding to the set of quantum bit values. The comparison block is configured to identify differences between the set of quantum bit values and the prior set of quantum bit values. The tree pipeline configured to rank the differences identified. The serializer is configured to serialize the differences identified in order by rank.

Growing community of inventors

Los Angeles, CA, United States of America

Michele Reilly