A scheme for two-photon lasing with two coupled flux qubits in circuit quantum electrodynamics<xref ref-type="fn" rid="cpb142316fn1">*</xref>

A scheme for two-photon lasing with two coupled flux qubits in circuit quantum electrodynamics*

Huang Wen^a),^b), Zou Xu-Bo^a),^b)†, Guo Guang-Can^a),^b)

The time evolution of the variance Δ X ( ϕ ). The solid (dashed) lines correspond to the minimum (maximum) value of the quadrature Δ X ( ϕ ) ( Δ X ( ϕ + π /2)). The blue lines correspond to κ = 0.08 g , γ = 0.05 g , p = 0.5 g , and the green lines correspond to κ = 0.02 g , γ = 0.01 g , p = 0.1 g . The other parameters are J = 3.8 (2 π GHz), δ = 0. The horizontal dashed line indicates the shot-noise limit.