Tunable and nonlinearity-enhanced dispersive-plus-dissipative coupling in photon-pressure circuits

Area of Science:

• Quantum physics
• Superconducting circuits
• Optomechanics

Background:

• Photon-pressure circuits are circuit implementations of the cavity optomechanical Hamiltonian.
• They are explored for qubit readout, quantum photonics, and dark matter axion detection.
• Superconducting circuits offer design flexibility for exploring optomechanical Hamiltonians.

Purpose of the Study:

• To realize a novel photon-pressure platform for enhanced circuit interactions.
• To investigate unusual parameter regimes of the optomechanical Hamiltonian.
• To explore nonlinear enhancements of coupling rates.

Main Methods:

• Implemented a photon-pressure platform with interacting GHz and MHz superconducting circuits.
• Utilized magnetic-flux-tunable dispersive and dissipative photon-pressure.
• Leveraged nonlinearities of the GHz-mode to enhance coupling rates.

Main Results:

• Achieved multi-photon coupling rates scaling stronger than the usual dependence on pump photon number.
• Demonstrated a Fano-like response in photon-pressure induced transparency via interference.
• Observed modified dynamical backaction, including parametric instability.

Conclusions:

• The realized platform offers enhanced coupling and novel phenomena in circuit optomechanics.
• Nonlinearities significantly boost photon-pressure interactions.
• The system shows potential for advanced quantum technologies and sensitive detection.