| Superconducting circuit is a leading candidate in the race to build a quantum computer.With the rapid increase in the number of the qubits on the quantum chips,the non-ideal control and parasitic interaction have become a bottleneck for further scaling up.High-quality,high-scalability control is one of research focus in the field.The parametric control scheme is one of the mainstream,due to the following advantages:1 allivating the frequency crowding problem.Since parametric control are based on sideband interaction,the frequency of the qubits does not need to be tuned close to resonance and unwanted level crossings are avoided.2.insensitive to flux cross talk due to the frequency-selective control.3.immune to long-time-scale pulse distortions,which are related to low frequency response of the control line.In this thesis,the first three chapters introduce the basic theory and quantum experimental platform of superconducting quantum computing.After that,we discuss the further extension of parametric control in superconducting circuit.First,we introduce a universal control scheme for superconducting circuits based on parametric modulation.By introducing a global pump signal,the scheme greatly simplifies the control circuit and avoids the complex IQ calibrations.The fidelity analysis proves its potential for a broad application.Second,we propose a superadiabatic two-qubit gate scheme,ultilizing the equivilantly tunable interaction stength of parametric control.We demonstrate it in a superconducting circuit with a fidelity mainly limited by decoherence.The gate scheme posesses strong robustness against parameter fluctuation with a relative fast speed,as demonstrated in the experiments.Third,we realize coherent state transfer between two qubits via stimulated Raman aidabatic passage(STIRAP).The STIRAP Hamiltonian is construted with specific parametric modualtion on the coupler.The scheme has better robustness and comparable speed,compared to nonadiabatic protocols in the same structure. |
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