Hybrid quantum systems with circuit quantum electrodynamics

Tunable magnon-magnon coupling in synthetic antiferromagnets

“…Although the coupling phenomena could be phenomenologically explained by a classical coupled-oscillator picture in general, microscopic descriptions of this type of hybridization are rich, offering novel functionalities of state control and energy/information transfer. For example, strong coupling of light-matter interaction is envisaged to offer fast and protected quantum information processing [2][3][4]. Within this expanding research domain, strong coupling between microwave photons and collective spins in magnetically ordered systems has been extensively studied in recent years [5][6][7][8].…”

Dissipation-Based Quantum Sensing of Magnons with a Superconducting Qubit

“…Superconducting qubits are attractive candidates for quantum sensors [1][2][3][4][5][6][7][8] as their large electric dipole moment enables strong coupling to electromagnetic fields [9,10]. Recent developments of hybrid quantum systems extend the range of applicability of qubits as quantum sensors through coupling the qubits to additional degrees of freedom [11][12][13][14][15][16].…”

Emergent PT symmetry in a double-quantum-dot circuit QED setup

“…We further explore signatures of exceptional points on tuning the coupling between cavities λ and the loss at the right cavity κ 2 . This setup can be realized in state-of-the-art circuit QED platforms [74][75][76][77][78]. In situ tuning of coupling between cQED resonators, as well as of the resonator losses, has been reported previously in experiments [67,[79][80][81][82].…”

“…The setup we consider consists of a solidstate double quantum dot (DQD) connected to two coupled circuit-QED (cQED) cavities. In recent years, a DQD in a cQED cavity has been well characterized both theoretically and experimentally [75][76][77]89,92,93,[101][102][103]. It is known that when the DQD is voltage biased via electronic leads under suitable conditions, it can be population inverted and can act as a widely controllable gain medium [70,72,[93][94][95].…”