$Q_{k}$’s to their drive ports $P_{k}$’s. Bottom: How much of the drive voltage leaks into other qubits in the upper row in the 2x8 multi-qubit device on the top figure above when only the qubit $Q_{1}$ is excited through its drive port $P_{1}$: classical crosstalk decays exponentially as a function of distance from the qubit $Q_{1}$ to the right in the first row of the circuit in the figure on the top. ](figs/xtalk_2by8_drives "fig:")

In this section we augment our model for the 2x8 multi-qubit device by adding the readout resonators and the drive ports as shown on the left in Fig. and apply the the formula in Eq. to evaluate the cross-talk in the device. We plot $X_{1k}$ which gives the crosstalk between the drive line of the qubit $Q_{1}$ and the other qubits on the first row in Fig. as a function of the qubit label $k=2,\ldots,8$ in Fig. .

\[sec:Purcell-rates\]Purcell Loss Rates of The Qubit Modes
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Qubits are coupled to external electronics for their readout and control. In Section \[sec:Voltage-couplings\] we analyzed couplings of the qubits to voltage drives. The same coupling mechanism causes relaxation of the excitations in the qubit modes which is called the 