Systems, devices, computer-implemented methods, and/or computer program products that facilitate dynamic control of ZZ interactions for quantum computing devices. In one example, a quantum device can comprise a biasing component that is operatively coupled to first and second qubits via respective first and second drive lines. The biasing component can facilitate dynamic control of ZZ interactions between the first and second qubits using continuous wave (CW) tones applied via the respective first and second drive lines.

A method of performing computation using a hybrid quantum-classical computing system including a classical computer, a system controller, and a quantum processor includes identifying a computational problem to be solved and a quantum algorithm to be used to solve the computational problem, detecting one or more faulty two-qubit gates among a plurality of two-qubit gates that can be applied to pairs of qubits in the quantum processor, compiling a computational task to solve the computational problem based on the quantum algorithm into a series of logic gates, including single-qubit gates and two-qubit gates that exclude the detected one or more faulty two-qubit gates, executing the series of logic gates on the quantum processor, measuring one or more of the qubits in the quantum processor, and outputting a solution to the identified computational problem derived from the measured results of the one or more of the qubits in the quantum processor.

A method may include: a computer program populating a Hermitian matrix A with input data; calculating an upper bound a for a maximum eigenvalue for the Hermitian matrix A; initializing a time evolution value t=1/a; generating a first quantum computer program using the time evolution value t; communicating the first quantum computer program to a quantum computer; receiving a result including a binary value for each n-bit string and a probability for each binary value; converting each binary value into an integer; identifying a maximum absolute value of the integers; determining a value x for the maximum absolute value of all of the integers; updating the time evolution value t based on the value of x; generating a second quantum computer program using the updated time evolution value t; and communicating, by the classical computer program, the second quantum computer program to the quantum computer.

Apparatus and method for dynamically adjusting a quantum computer clock frequency. For example, one embodiment of an apparatus comprises: a quantum execution unit to execute quantum operations specified by a quantum runtime; a qubit drive controller to translate the quantum operations into physical pulses directed to qubits on a quantum chip at a first cycle frequency; a spin echo sequencer to issue spin echo command sequences to cause the qubit drive controller to generate a sequence of spin echo pulses at the first cycle frequency; and qubit measurement circuitry to measure the qubits and to store qubit timing data for each qubit, the qubit timing data indicating a coherence time or an amount of computational time available for each qubit to perform quantum operations.

Apparatus and method for dynamically adjusting a quantum computer clock frequency. For example, one embodiment of an apparatus comprises: a quantum execution unit to execute quantum operations specified by a quantum runtime; a qubit drive controller to translate the quantum operations into physical pulses directed to qubits on a quantum chip at a first cycle frequency; a spin echo sequencer to issue spin echo command sequences to cause the qubit drive controller to generate a sequence of spin echo pulses at the first cycle frequency; and qubit measurement circuitry to measure the qubits and to store qubit timing data for each qubit, the qubit timing data indicating a coherence time or an amount of computational time available for each qubit to perform quantum operations.

Method for sending first data as quantum information in qubits (Iφ>) and classical second data (S.sub.i) over a quantum channel (12; 12a; 12b), in particular in quantum information communication systems (10; 10a; 10b), which includes applying QECC encoding (111) to said qubits ((Iφ>) obtaining quantum information codewords (Iψ>), wherein said method (200; 300) includes applying (210) intentional errors (P.sub.i) with error syndromes (S.sub.i) representing said second classical data to said quantum information code-words ((Iψ>) obtaining quantum information codewords with intentional errors (P.sub.1) applied upon (P.sub.iIψ.sub.i>), and transmitting (220) from a transmitting side (11; 11a; 11b) said quantum information codewords with intentional errors applied upon (P.sub.iIψ.sub.i>) over said quantum channel (12; 12a) which outputs received codewords (P.sub.iIψ.sub.i>;E.sub.iP.sub.iIψ.sub.i>) at a receiving side (13; 13b), computing (230; 330) error syndromes (S.sub.i,R.sub.i) from said received codewords (P.sub.iIψ.sub.i>;E.sub.iP.sub.iIψ.sub.i>), performing a QECC error correction operation (250; 350) on said received codewords (P.sub.iIψ.sub.i>;E.sub.iP.sub.iIψ.sub.i>) by applying a correction operator (P.sub.i.sup.+; P.sub.i.sup.+E.sub.i.sup.+) obtained at least by said computed syndromes (S.sub.i; R.sub.i) to obtain corrected codewords (Iψ.sub.i>), outputting (260; 360) said corrected codewords (Iψ.sub.i>) and said computed syndromes (S.sub.i).

Method for sending first data as quantum information in qubits (Iφ>) and classical second data (S.sub.i) over a quantum channel (12; 12a; 12b), in particular in quantum information communication systems (10; 10a; 10b), which includes applying QECC encoding (111) to said qubits ((Iφ>) obtaining quantum information codewords (Iψ>), wherein said method (200; 300) includes applying (210) intentional errors (P.sub.i) with error syndromes (S.sub.i) representing said second classical data to said quantum information code-words ((Iψ>) obtaining quantum information codewords with intentional errors (P.sub.1) applied upon (P.sub.iIψ.sub.i>), and transmitting (220) from a transmitting side (11; 11a; 11b) said quantum information codewords with intentional errors applied upon (P.sub.iIψ.sub.i>) over said quantum channel (12; 12a) which outputs received codewords (P.sub.iIψ.sub.i>;E.sub.iP.sub.iIψ.sub.i>) at a receiving side (13; 13b), computing (230; 330) error syndromes (S.sub.i,R.sub.i) from said received codewords (P.sub.iIψ.sub.i>;E.sub.iP.sub.iIψ.sub.i>), performing a QECC error correction operation (250; 350) on said received codewords (P.sub.iIψ.sub.i>;E.sub.iP.sub.iIψ.sub.i>) by applying a correction operator (P.sub.i.sup.+; P.sub.i.sup.+E.sub.i.sup.+) obtained at least by said computed syndromes (S.sub.i; R.sub.i) to obtain corrected codewords (Iψ.sub.i>), outputting (260; 360) said corrected codewords (Iψ.sub.i>) and said computed syndromes (S.sub.i).

A parameter calibration method is provided. The parameter calibration method includes: obtaining a control parameter to be calibrated; determining a simulation running error corresponding to a quantum chip; determining calibration data corresponding to the control parameter to be calibrated based on the simulation running error; and obtaining a calibrated control parameter by calibrating the control parameter to be calibrated based on the calibration data, wherein the calibrated control parameter is used for controlling operation of the quantum chip.

A parameter calibration method is provided. The parameter calibration method includes: obtaining a control parameter to be calibrated; determining a simulation running error corresponding to a quantum chip; determining calibration data corresponding to the control parameter to be calibrated based on the simulation running error; and obtaining a calibrated control parameter by calibrating the control parameter to be calibrated based on the calibration data, wherein the calibrated control parameter is used for controlling operation of the quantum chip.

A system obtains a first operator that produces a superposition state of a plurality of random variables. The system performs iteration of a first operation and a second operation on an initial quantum state using a state maintaining unit to produce a final quantum state. The first operation produces a second state by performing a computation that inverts a first state with respect to a state obtained by applying a Hermitian conjugate of the first operator to a quantum state where the last bit of a bit string is 0. The second operation produces a new first state by performing a computation that inverts the second state with respect to the first state. The system measures the bit string in the final quantum state, records the number of hits that is the number of times a quantum state where all bits of the bit string are 0 is observed, and calculate an expectation value of the random variables by maximum likelihood estimation according to the number of hits.