University System of Maryland

Duke University

Ionq, Inc.

University of British Columbia

Other

Government of the United States of America, As Represented by the Secretary of Commerce

Christopher R Monroe

Jungsang Kim

Norbert M Linke

Ksenia Sosnova

Martin Lichtman

Ismail Volkan Inlek

Clayton Crocker

Shantanu Debnath

Marko Cetina

Caroline Figgatt

Dmitri Maslov

David Wong-Campos

Aaron Ostrander

Kevin A Landsman

Daiwei Zhu

Jiehang Zhang

Guido Pagano

Antonios Kyprianidis

Patrick Michael Becker

Jaime David Wong-Campos

Kenneth Brown

Robert Raussendorf

Paul W Hess

Harvey B Kaplan

Wen Lin Tan

Philip J Richerme

Kale Johnson

Yunseong Nam

Kai Hudek

Michael Lurie Goldman

Jonathan Albert Mizrahi

Kristin Marie Beck

Alexey Vyacheslavovich Gorshkov

Sarah Margaret Kreikemeier

Zachary David Eldredge

Kevin Chengming Qian

Wenchao Ge

James Vincent Porto, Iii

Kristen Beck

The disclosure describes an adaptive and optimal imaging of individual quantum emitters within a lattice or optical field of view for quantum computing. Advanced image processing techniques are described to identify individual optically active quantum bits (qubits) with an imager. Images of individual and optically-resolved quantum emitters fluorescing as a lattice are decomposed and recognized based on fluorescence. Expected spatial distributions of the quantum emitters guides the processing, which uses adaptive fitting of peak distribution functions to determine the number of quantum emitters in real time. These techniques can be used for the loading process, where atoms or ions enter the trap one-by-one, for the identification of solid-state emitters, and for internal state-detection of the quantum emitters, where each emitter can be fluorescent or dark depending on its internal state. This latter application is relevant to efficient and fast detection of optically active qubits in quantum simulations and quantum computing.

Adaptive and optimal imaging of quantum optical systems for quantum computing

Aspects of the present disclosure describe techniques that involve an active stabilization of coherent controllers using nearby qubits. In an aspect, a quantum information processing (QIP) system for stabilizing phase damping in qubits is described that provides a first and a second qubit ion, measuring magnetic field fluctuations using the second qubit ion, and generates one or more magnetic fields based on the measured magnetic field fluctuations, the one or more magnetic fields being applied near the first qubit ion to cancel the magnetic field fluctuations to stabilize the phase damping of the first qubit ion. Another such QIP system performs provides a first and a second qubit ion, locks a local oscillator to a frequency reference associated with the second qubit ion, and tracks, using the local oscillator, a frequency of the first qubit ion based on the frequency reference. Methods associated with these QIP systems are also described.

Active stabilization of coherent controllers using nearby qubits

A modular quantum computer architecture is developed with a hierarchy of interactions that can scale to very large numbers of qubits. Local entangling quantum gates between qubit memories within a single modular register are accomplished using natural interactions between the qubits, and entanglement between separate modular registers is completed via a probabilistic photonic interface between qubits in different registers, even over large distances. This architecture is suitable for the implementation of complex quantum circuits utilizing the flexible connectivity provided by a reconfigurable photonic interconnect network. The subject architecture is made fault-tolerant which is a prerequisite for scalability. An optimal quantum control of multimode couplings between qubits is accomplished via individual addressing the qubits with segmented optical pulses to suppress crosstalk in each register, thus enabling high-fidelity gates that can be scaled to larger qubit registers for quantum computation and simulation.

Fault-tolerant scalable modular quantum computer architecture with an enhanced control of multi-mode couplings between trapped ion qubits

The disclosure describes aspects of using multiple species in trapped-ion nodes for quantum networking. In an aspect, a quantum networking node is described that includes multiple memory qubits, each memory qubit being based on aYbatomic ion, and one or more communication qubits, each communication qubit being based on aBaatomic ion. The memory and communication qubits are part of a lattice in an atomic ion trap. In another aspect, a quantum computing system having a modular optical architecture is described that includes multiple quantum networking nodes, each quantum networking node including multiple memory qubits (e.g., based on aYbatomic ion) and one or more communication qubits (e.g., based on aBaatomic ion). The memory and communication qubits are part of a lattice in an atomic ion trap. The system further includes a photonic entangler coupled to each of the multiple quantum networking nodes.

Quantum network node and protocols with multiple qubit species

The disclosure describes various aspects of optical control of atomic quantum bits (qubits) for phase control operations. More specifically, the disclosure describes methods for coherently controlling quantum phases on atomic qubits mediated by optical control fields, applying to quantum logic gates, and generalized interactions between qubits. Various attributes and settings of optical/qubit interactions (e.g., atomic energy structure, laser beam geometry, polarization, spectrum, phase, background magnetic field) are identified for imprinting and storing phase in qubits. The disclosure further describes how these control attributes are best matched in order to control and stabilize qubit interactions and allow extended phase-stable quantum gate sequences.

Optical control of atomic quantum bits for phase control of operation

The disclosure describes various aspects related to enabling effective multi-qubit operations, and more specifically, to techniques for enabling parallel multi-qubit operations on a universal ion trap quantum computer. In an aspect, a method of performing quantum operations in an ion trap quantum computer or trapped-ion quantum system includes implementing at least two parallel gates of a quantum circuit, each of the at least two parallel gates is a multi-qubit gate, each of the at least two parallel gates is implemented using a different set of ions of a plurality of ions in a ion trap, and the plurality of ions includes four or more ions. The method further includes simultaneously performing operations on the at least two parallel gates as part of the quantum operations. A trapped-ion quantum system and a computer-readable storage medium corresponding to the method described above are also disclosed.

Parallel multi-qubit operations on a universal ion trap quantum computer

A Heisenberg scaler reduces noise in quantum metrology and includes: a stimulus source that provides physical stimuli; a physical system including quantum sensors that receive a first and second physical stimuli; produces a measured action parameter; receives an perturbation pulse; and produces modal amplitude; an estimation machine that: receives the measured action parameter and produces a zeroth-order value from the measured action parameter; a gradient analyzer that: receives the measured action parameter and produces the measured action parameter and a gradient; the sensor interrogation unit that: receives the modal amplitude; receives the gradient and the measured action parameter; produces the perturbation pulse; and produces a first-order value from the modal amplitude, the gradient, and the measured action parameter; a Heisenberg determination machine that: receives the zeroth-order value; receives the first-order value; and produces a physical scalar from the zeroth-order value and the first-order value.

Heisenberg scaler

Aspects of the present disclosure describe techniques for controlling quantum states of ions in an ion chain for a quantum operation. For example, a method is described that includes providing, from a first direction, a global optical beam to the ions in the ion chain, and providing, from a second direction different from the first direction, to each ion in a subset of the ions in the ion chain, a respective addressing optical beam. The method further includes dynamically controlling each of the addressing optical beams being provided by using a respective channel in a multi-channel acousto-optic modulator (AOM) to implement, with the ion chain, one or more quantum gates in a sequence of quantum gates of the quantum operation. Aspects of a quantum information processing (QIP) system that includes the multi-channel AOM for performing the method are also described.

Multi-qubit control with acousto-optic modulators

Growing community of inventors

Columbia, MD, United States of America

Christopher R Monroe