Abstract: A MEMS resonator device includes: (i) a support structure, (ii) a resonator element doped with at least one of N-type or P-type dopants, wherein a doping concentration of the at least one of N-type or P-type dopants causes a closely temperature-compensated mode in which (a) an absolute value of a first order temperature coefficient of frequency of the resonator element is reduced to a first value below a threshold value and (b) an absolute value of a second order temperature coefficient of frequency of the resonator element is reduced to about zero, and wherein an anchor decoupler region formed on the resonator element causes the absolute value to be further reduced to a second value, and (iii) at least one anchor coupling the resonator element to the support structure, wherein the anchor decoupler region is formed on the resonator element at least partially surrounding the at least one anchor.

Abstract: Devices, systems, and methods that include a qubit coupled to a projective-source digital-to-analog converter (PSDAC) for projective measurement of the qubit. A change in flux state of the PSDAC from a first flux state to a second flux state generates a fast-flux step or fast-step waveform that can be applied to the qubit to perform projective measurement of the qubit. For a quantum processor that includes a set of qubits wherein each qubit is coupled to a respective PSDAC, a shared trigger line can activate each PSDAC to generate a respective fast-flux step or fast-step waveform. Synchronization devices can synchronize the fast-flux steps or fast-step waveforms, allowing for projective readout of the set of qubits.

Abstract: An example silicon MEMS resonator device includes a support structure, a resonator element with at least one associated eigenmode of vibration, at least one anchor coupling the resonator element to the support structure, at least one driving electrode, and at least one sense electrode. The resonator element is homogeneously doped with N-type or P-type dopants to a doping concentration that causes a closely temperature-compensated mode in which (i) an absolute value of a first order temperature coefficient of frequency of the resonator element is reduced to a first value below a threshold value and (ii) an absolute value of a second order temperature coefficient of frequency of the resonator element is reduced to about zero. Further, a geometry of the resonator element is chosen such that the absolute value of the first order temperature coefficient of frequency is further reduced to a second value smaller than the first value.

Abstract: Devices, systems, and methods that include a qubit coupled to a projective-source digital-to-analog converter (PSDAC) for projective measurement of the qubit. A change in flux state of the PSDAC from a first flux state to a second flux state generates a fast-flux step or fast-step waveform that can be applied to the qubit to perform projective measurement of the qubit. For a quantum processor that includes a set of qubits wherein each qubit is coupled to a respective PSDAC, a shared trigger line can activate each PSDAC to generate a respective fast-flux step or fast-step waveform. Synchronization devices can synchronize the fast-flux steps or fast-step waveforms, allowing for projective readout of the set of qubits.