TY - JOUR
T1 - Controllable coupling between a nanomechanical resonator and a coplanar-waveguide resonator via a superconducting flux qubit
AU - Xiong, Wei
AU - Jin, Da Yu
AU - Jing, Jun
AU - Lam, Chi Hang
AU - You, J. Q.
PY - 2015/9/21
Y1 - 2015/9/21
N2 - We study a tripartite quantum system consisting of a coplanar-waveguide (CPW) resonator and a nanomechanical resonator (NAMR) connected by a flux qubit, where the flux qubit has a large detuning from both resonators. By a unitary transformation and a second-order approximation, we obtain a strong and controllable (i.e., magnetic-field-dependent) effective coupling between the NAMR and the CPW resonator. Due to the strong coupling, vacuum Rabi splitting can be observed from the voltage-fluctuation spectrum of the CPW resonator. We further study the properties of single-photon transport as inferred from the reflectance or equivalently the transmittance. We show that the reflectance and the corresponding phase-shift spectra both exhibit doublet of narrow spectral features due to vacuum Rabi splitting. By tuning the external magnetic field, the reflectance and the phase shift can be varied from 0 to 1 and -π to π, respectively. The results indicate that this hybrid quantum system can act as a quantum router.
AB - We study a tripartite quantum system consisting of a coplanar-waveguide (CPW) resonator and a nanomechanical resonator (NAMR) connected by a flux qubit, where the flux qubit has a large detuning from both resonators. By a unitary transformation and a second-order approximation, we obtain a strong and controllable (i.e., magnetic-field-dependent) effective coupling between the NAMR and the CPW resonator. Due to the strong coupling, vacuum Rabi splitting can be observed from the voltage-fluctuation spectrum of the CPW resonator. We further study the properties of single-photon transport as inferred from the reflectance or equivalently the transmittance. We show that the reflectance and the corresponding phase-shift spectra both exhibit doublet of narrow spectral features due to vacuum Rabi splitting. By tuning the external magnetic field, the reflectance and the phase shift can be varied from 0 to 1 and -π to π, respectively. The results indicate that this hybrid quantum system can act as a quantum router.
UR - http://www.scopus.com/inward/record.url?scp=84943158405&partnerID=8YFLogxK
U2 - 10.1103/PhysRevA.92.032318
DO - 10.1103/PhysRevA.92.032318
M3 - Journal article
SN - 1050-2947
VL - 92
JO - Physical Review A - Atomic, Molecular, and Optical Physics
JF - Physical Review A - Atomic, Molecular, and Optical Physics
IS - 3
M1 - 032318
ER -