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Proposal for Coupling Superconducting Qubits via a Squeezed Cavity


  Inbar Shani  ,  Emanuele G. Dalla Torre   ,  Michael Stern   
 Bar Ilan University
QUEST - Quantum Entanglement Science & Technology
BINA, Bar-Ilan institute of Nanotechnology and Advanced Materials

Abstract

 

Efficient and scalable two-qubit gates are the key ingredients to operate quantum processors. In recent years, many schemes for performing such gates have been proposed and implemented: (i) tuning the qubit resonance frequencies via DC pulses [1,2], (ii) dressing the qubits by applying a microwave drive (FLICFORQ [3-5] or Cross-Resonance [6] techniques), or (iii) using various sub-circuits to control the qubit-qubit interaction [7-8].  Each of these techniques presents advantages and disadvantages in terms of robustness and fidelities.

Here, we propose to study a different approach by considering the mediated interaction between two qubits through a squeezed cavity.  In our proposed scheme, the cavity is parametrically driven with an appropriate frequency and amplitude in order to establish an effective resonance condition between two fixed off-resonant qubits.

 

References

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  4. Rigetti, Chad, and Michel Devoret. "Fully microwave-tunable universal gates in superconducting qubits with linear couplings and fixed transition frequencies." Physical Review B 81,13 (2010).
  5. Caldwell, Riggeti, et al. "Parametrically activated entangling gates using transmon qubits." Physical Review Applied 10,3 (2018).
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