Housing Qubit Devices in an Electromagnetic Waveguide System

Abstract

In some aspects, a quantum computing system includes an electromagnetic waveguide system. The waveguide system has an interior surface that defines an interior volume of intersecting waveguides. Qubit devices are housed in the waveguide system. In some cases, the intersecting waveguides each define a cutoff frequency, and the qubit devices have qubit operating frequencies below the cutoff frequency. In some cases, coupler devices are housed in the waveguide system; each coupler device is configured to selectively couple a pair of neighboring qubit devices based on control signals received from a control source.

1 - 108 . (canceled) 
     
     
         109 . A quantum computing method comprising:
 receiving, at a coupler device in a quantum processor cell assembly, a coupler control signal from a control source external to the quantum processor cell assembly, the coupler device housed between qubit devices that have respective qubit operating frequencies, the coupler control signal causing the coupler device to produce an electromagnetic interaction between the qubit devices; and   suppressing, by a waveguide structure between the qubit devices, signal propagation at the qubit operating frequencies.   
     
     
         110 . The quantum computing method of  claim 109 , wherein each qubit device comprises an electronic circuit that defines the qubit operating frequency of the qubit device. 
     
     
         111 . The quantum computing method of  claim 109 , further comprising receiving a qubit control signal at one of the qubit devices, wherein the qubit control signal causes the qubit device to process information encoded in the qubit device. 
     
     
         112 . The quantum computing method of  claim 109 , further comprising producing qubit readout signals by operation of readout devices housed in the processor cell assembly, the qubit readout signals produced in response to readout control signals delivered to the readout devices based on interactions between the readout devices and the qubit devices. 
     
     
         113 . The quantum computing method of  claim 109 , wherein an electromagnetic waveguide system comprises an interior surface that defines an interior volume of intersecting waveguides, and the waveguide structure that suppresses propagation of signals comprises a subsection of electromagnetic waveguide system. 
     
     
         114 . The quantum computing method of  claim 109 , comprising:
 receiving qubit control signals at qubit devices housed in an electromagnetic waveguide system in the quantum processor cell assembly; and   receiving coupler control signals at coupler devices housed between respective pairs of the qubit devices in the electromagnetic waveguide system.   
     
     
         115 . The quantum computing method of  claim 114 , wherein the electromagnetic waveguide system comprises a two-dimensional waveguide lattice that includes a first subset of waveguides intersecting a second subset of waveguides at waveguide intersections in the quantum processor cell assembly, and the qubit devices and coupler devices are arranged in alignment with the two-dimensional waveguide lattice. 
     
     
         116 . The quantum computing method of  claim 115 , comprising suppressing signal propagation at one or more qubit operating frequencies by operation of the electromagnetic waveguide system. 
     
     
         117 . A quantum computing method comprising:
 encoding information in qubit devices housed in an electromagnetic waveguide system in a quantum processor cell assembly, the qubit devices having respective qubit operating frequencies, the electromagnetic waveguide system configured to suppress signal propagation over a frequency range that includes the qubit operating frequencies; and   processing the information encoded in the qubit devices by operation of coupler devices housed in the electromagnetic waveguide system between respective pairs of the qubit devices.   
     
     
         118 . The quantum computing method of  claim 117 , comprising processing the information encoded in the qubit devices by operation of qubit devices. 
     
     
         119 . The quantum computing method of  claim 117 , further comprising extracting output information from the qubit devices by operation of readout devices housed in the quantum processor cell assembly. 
     
     
         120 . The quantum computing method of  claim 117 , comprising executing a quantum algorithm on the information encoded in the qubit devices, wherein the quantum algorithm includes one or more multi-qubit gates that are executed by operation of the coupler devices. 
     
     
         121 . The quantum computing method of  claim 120 , wherein the quantum algorithm includes one or more single-qubit gates that are executed by operation of the qubit devices. 
     
     
         122 - 128 . (canceled) 
     
     
         129 . A quantum computing system comprising:
 a quantum processor cell that houses qubit devices and coupler devices in an electromagnetic waveguide system, the qubit devices and the coupler devices forming a multi-dimensional device lattice comprising multiple adjoining unit cells, each unit cell of the device lattice comprising at least one of the qubit devices and at least one of the coupler devices; and   a control system communicably coupled to the quantum processor cell and configured to control the qubit devices.   
     
     
         130 . The quantum computing system of  claim 129 , wherein the quantum processor cell houses readout devices, and each unit cell of the lattice includes at least one of the readout devices. 
     
     
         131 . The quantum computing system of  claim 129 , wherein the electromagnetic waveguide system comprises a multi-dimensional waveguide lattice formed by intersecting waveguide sections, wherein the device lattice is aligned in the waveguide lattice. 
     
     
         132 . The quantum computing system of  claim 129 , wherein the multi-dimensional device lattice comprises a two-dimensional device lattice, and each unit cell comprises two or more coupler devices. 
     
     
         133 . The quantum computing system of  claim 129 , wherein the multi-dimensional device lattice comprises a three-dimensional device lattice, and each unit cell comprises three or more coupler devices. 
     
     
         134 . The quantum computing system of  claim 129 , further comprising a signal delivery system that communicates signals between the control system and the quantum processor cell.