Demodulation and smoothing of amplitude, frequency, and phase modulated pulses for optimal implementation of entangling gates in ion trap quantum computers
AssigneeIonQ, Inc.
InventorsReinhold BLUMEL, Nikodem GRZESIAK, Yunseong NAM
Life of this patent
Estimating the term…
Abstract
Embodiments described herein are generally related to a method and a system for constructing and delivering a pulse to perform an entangling gate operation between two trapped ions during a quantum computation, and more specifically, to a method of demodulating and spline interpolating a pulse that can be practically implemented in the system while increasing the fidelity of the entangling gate operation, or the probability that at least two ions are in the intended qubit state(s) after performing the entangling gate operation between the two ions.
Claims20
A method of performing a computation using a quantum computer, comprising:
- computing a phase function and an amplitude function of a laser pulse to cause entangling interaction between a pair of trapped ions of a plurality of trapped ions, each of the plurality of trapped ions having two frequency-separated states defining a qubit;
- smoothing the computed phase function of the laser pulse;
- computing a detuning frequency function of the laser pulse based on the smoothed phase function of the laser pulse;
- spline interpolating the computed detuning frequency function of the laser pulse;
- and
- applying a pulse having the spline interpolated detuning frequency function and the amplitude function to the pair of trapped ions.
A non-transitory computer-readable medium including computer program instructions, which when executed by a processor, cause the processor to:
- compute a phase function and an amplitude function of a laser pulse to cause entangling interaction between a pair of trapped ions of a plurality of trapped ions, each of the plurality of trapped ions having two frequency-separated states defining a qubit;
- smooth the computed phase function of the laser pulse;
- compute a detuning frequency function of the laser pulse based on the smoothed phase function of the laser pulse;
- spline interpolate the computed detuning frequency function of the laser pulse;
- and
- apply a laser pulse having the spline interpolated detuning frequency function and the amplitude function to the pair of trapped ions.
A quantum computing system, comprising:
- a plurality of trapped ions, each of the trapped ions having two hyperfine states defining a qubit;
- and
- a controller comprising non-volatile memory having a number of instructions stored therein which, when executed by a processor, causes the quantum computing system to perform operations comprising:
- computing a phase function and an amplitude function of a laser pulse to cause entangling interaction between a pair of trapped ions of the plurality of trapped ions;
- smoothing the computed phase function of the laser pulse;
- computing a detuning frequency function of the laser pulse based on the smoothed phase function of the laser pulse;
- spline interpolating the computed detuning frequency function of the laser pulse;
- and
- applying a laser pulse having the spline interpolated detuning frequency function and the amplitude function to the pair of trapped ions.
Dependencies are inferred from the claim text.