About this Research Topic
Superconducting quantum circuits constitute a leading contender in the race to achieve fault-tolerant quantum computation. However, the up-scaling of superconducting quantum processors presents several engineering challenges. For example, the dimensions of the chips containing superconducting qubits are not able to be expanded indefinitely as several problems arise during this process, including the coupling of the qubits to the spurious chip modes. Hence, a single chip can contain only a finite number of qubits and, therefore, it is essential to generate entanglement over long distances to link qubits residing within different chips. The possible variation in distances between qubits requires the application of several different solution strategies.
To facilitate the continued development of superconducting quantum processors it is necessary to generate entanglement and/or realize state-transfer between qubits within different superconducting quantum chips. Novel qubit couplers and entanglement generation protocols must be designed to overcome various issues associated with coupling the qubits over long distances.
In particular, qubits are exposed to the multi-mode spectrum associated with long lossy cables and their decay into these lossy modes limits their coherence time. The design of the novel coupling structures through the application of microwave engineering techniques will help in reducing the coupling of the qubits to the aforementioned lossy modes.
Adiabatic gate protocols have been shown to improve the coherence of the qubits and novel two-qubit gate proposals may mitigate the channel loss.
For solutions employing optical links, the fidelity exhibited by the microwave to optical photon conversion is crucial.
As the communication technologies which are employed during coupling vary depending on the distance over which the qubits need to be coupled, we would like to maintain a broad scope for this collection. For example, in the case of relatively short distances and for chips residing in the same dilution fridge microwave, waveguides and coaxial cables will be employed, whereas for qubits housed in different dilution fridges, cryogenic microwave links or optical links may be necessary. In the latter case, microwave to optical photon conversion will be required and, therefore, manuscripts concerning optical transducer links, microwave-to-optical photon conversion, nanomechanical resonators, quantum networks are also welcomed. We also particularly encourage the submission of articles pertaining to the issue of cable loss.
To facilitate the continued development of superconducting quantum processors it is necessary to generate entanglement and/or realize state-transfer between qubits within different superconducting quantum chips. Novel qubit couplers and entanglement generation protocols must be designed to overcome various issues associated with coupling the qubits over long distances.
In particular, qubits are exposed to the multi-mode spectrum associated with long lossy cables and their decay into these lossy modes limits their coherence time. The design of the novel coupling structures through the application of microwave engineering techniques will help in reducing the coupling of the qubits to the aforementioned lossy modes.
Adiabatic gate protocols have been shown to improve the coherence of the qubits and novel two-qubit gate proposals may mitigate the channel loss.
For solutions employing optical links, the fidelity exhibited by the microwave to optical photon conversion is crucial.
As the communication technologies which are employed during coupling vary depending on the distance over which the qubits need to be coupled, we would like to maintain a broad scope for this collection. For example, in the case of relatively short distances and for chips residing in the same dilution fridge microwave, waveguides and coaxial cables will be employed, whereas for qubits housed in different dilution fridges, cryogenic microwave links or optical links may be necessary. In the latter case, microwave to optical photon conversion will be required and, therefore, manuscripts concerning optical transducer links, microwave-to-optical photon conversion, nanomechanical resonators, quantum networks are also welcomed. We also particularly encourage the submission of articles pertaining to the issue of cable loss.
Keywords: Remote Entanglement, Quantum State Transfer, Modular Couplers, Superconducting Microwave Circuits, Quantum Microwave Engineering, Waveguide QED, Cryogenic Microwave Links, Quantum Networks, Quantum Links
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