Two-photon quantum Rabi model with superconducting circuits

Author(s)

Felicetti, S. ; Rossatto, D. Z. ; Rico, E. ; Solano, E. ; Forn-Diaz, P.

• Document type: Journal article
• Source: PHYSICAL REVIEW A; v. 97, n. 1, p. 11-pg., 2018-01-30.

Abstract

We propose a superconducting circuit to implement a two-photon quantum Rabi model in a solid-state device, where a qubit and a resonator are coupled by a two-photon interaction. We analyze the input-output relations for this circuit in the strong-coupling regime and find that fundamental quantum-optical phenomena are qualitatively modified. For instance, two-photon interactions are shown to yield a single-or two-photon blockade when a pumping field is either applied to the cavity mode or to the qubit, respectively. In addition, we derive an effective Hamiltonian for perturbative ultrastrong two-photon couplings in the dispersive regime, where two-photon interactions introduce a qubit-state-dependent Kerr term. Finally, we analyze the spectral collapse of the multiqubit two-photon quantum Rabi model and find a scaling of the critical coupling with the number of qubits. Using realistic parameters with the circuit proposed, three qubits are sufficient to reach the collapse point. (AU)

• FAPESP's process: 13/23512-7 - Circuit Quantum Electrodynamics: Bistability and Squeezed States
• Grantee: Daniel Zini Rossatto
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 14/24576-1 - Ultrastrong and deep strong coupling regimes in circuit quantum electrodynamics
• Grantee: Daniel Zini Rossatto
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor