This application discloses a fault tolerant computation method and device for a quantum Clifford circuit with reduced resource requirement. The method includes decomposing a quantum Clifford circuit into s logic Clifford circuits and preparing auxiliary quantum states corresponding to the s logic Clifford circuits. For each logic Clifford circuit, the method further includes teleporting an input quantum state corresponding to the logic Clifford circuit to an auxiliary qubit, processing a quantum state obtained after the teleportation by the logic Clifford circuit to obtain a corresponding output quantum state; measuring a corresponding error symptom based on the input quantum state and the auxiliary quantum state; and performing error correction on the output quantum state according to the error symptom to obtain an error-corrected output quantum state.

The examples disclosed herein provide classifying quantum errors. In particular, a classical computing system receives quantum error data from a first quantum computing device of a quantum computing system. The quantum error data includes error identification data and error correction data. The error identification data is associated with occurrence of a quantum error. The error correction data is associated with a corrective action taken by the first quantum computing device to correct the quantum error. The classical computing system determines an error type of the quantum error of the error identification data. The classical computing system associates an error classification tag with the quantum error data. The error classification tag identifies a quantum error type. The classical computing system sends the error classification tag to the first quantum computing device. The classical computing system processes a quantum computing request based on the error classification tag.

The examples disclosed herein provide classifying quantum errors. In particular, a classical computing system receives quantum error data from a first quantum computing device of a quantum computing system. The quantum error data includes error identification data and error correction data. The error identification data is associated with occurrence of a quantum error. The error correction data is associated with a corrective action taken by the first quantum computing device to correct the quantum error. The classical computing system determines an error type of the quantum error of the error identification data. The classical computing system associates an error classification tag with the quantum error data. The error classification tag identifies a quantum error type. The classical computing system sends the error classification tag to the first quantum computing device. The classical computing system processes a quantum computing request based on the error classification tag.

A quantum error correcting code with dynamically generated logical qubits is provided. When viewed as a subsystem code, the code has no logical qubits. Nevertheless, the measurement patterns generate logical qubits, allowing the code to act as a fault-tolerant quantum memory. Each measurement can be a two-qubit Pauli measurement.

A method includes receiving a plurality of quantum systems, wherein each quantum system of the plurality of quantum system includes a plurality of quantum sub-systems in an entangled state, and wherein respective quantum systems of the plurality of quantum systems are independent quantum systems that are not entangled with one another. The method further includes performing a plurality of joint measurements on different quantum sub-systems from respective ones of the plurality of quantum systems, wherein the joint measurements generate joint measurement outcome data and determining, by a decoder, a plurality of syndrome graph values based on the joint measurement outcome data.

One-dimensional and two-dimensional arrays of qubits are disclosed. The one-dimensional array includes two or more double-quantum dots embedded in silicon, the two or more double-quantum dots arranged in an Echelon formation, such that the distance between the two or more double-quantum dots is approximately 40 nm and the distance between the two quantum dots in each double-quantum dot is approximately 12 nm; two or more reservoirs to load electrons to the corresponding two or more double-quantum dots to form singlet-triplet qubits in each double-quantum dot; and two or more gates for controlling the formed singlet-triplet qubits. The two-dimensional array of qubits includes two or more layers of vertically-stacked one-dimensional arrays of qubits.

Methods and systems for performing a surface code error detection cycle. In one aspect, a method includes initializing and applying Hadamard gates to multiple measurement qubits; performing entangling operations on a first set of paired qubits, wherein each pair comprises a measurement qubit coupled to a neighboring data qubit in a first direction; performing entangling operations on a second set of paired qubits, wherein each pair comprises a measurement qubit coupled to a neighboring data qubit in a second or third direction, the second and third direction being perpendicular to the first direction, the second direction being opposite to the third direction; performing entangling operations on a third set of paired qubits, wherein each pair comprises a measurement qubit coupled to a neighboring data qubit in a fourth direction, the fourth direction being opposite to the first direction; applying Hadamard gates to the measurement qubits; and measuring the measurement qubits.

In one example described herein a system can receive, by a scheduler of a server, a request to execute a quantum algorithm. The system can determine, by the scheduler, a quantum computer system of a plurality of quantum computer systems to execute the quantum algorithm based on a database that stores associations between each quantum computer system of the plurality of quantum computer systems, at least one parameter associated with the quantum algorithm, and error information. The system can transmit, by the scheduler, the request to the quantum computer system for executing the quantum algorithm.

In one example described herein a system can receive, by a scheduler of a server, a request to execute a quantum algorithm. The system can determine, by the scheduler, a quantum computer system of a plurality of quantum computer systems to execute the quantum algorithm based on a database that stores associations between each quantum computer system of the plurality of quantum computer systems, at least one parameter associated with the quantum algorithm, and error information. The system can transmit, by the scheduler, the request to the quantum computer system for executing the quantum algorithm.

Apparatus and method for injected spin echo sequences in a quantum processor. For example, one embodiment of a processor includes a decoder to decode quantum instructions to generate quantum microoperations (uops) and to decode non-quantum instructions to generate non-quantum uops, execution circuitry to execute the quantum uops and non-quantum uops, and a corrective sequence data structure to identify and/or store corrective sets of uops for one or more of the quantum instructions. The decoder is to query the corrective sequence data structure upon receiving a first quantum instruction to determine if one or more corrective uops exist, and if the one or more corrective uops exist, the decoder is to submit the one or more corrective uops for execution by the execution circuitry.