Energy conversion from environmental fluctuations to coherent fields by Cooper-pair box quantum meta-materials

摘要： Electromagnetic waves propagating in open Cooper-Pair Boxes (CPBs) system is studied by using Maxwell-Bloch equations and Lindblad master equation. The results demonstrate an ensemble of CPBs as highly non-linear meta-material for electromagnetic waves. Incorporating the CPBs in a ring resonator or a Fabry-Perot cavity, one finds that: (1) With weak environmental couplings and CPBs in superconducting phase dominant regime, the non-linearity is enhanced and the system exhibits regular optical hysteresis. (2) With finite environmental couplings and CPBs in charge dominant regime, the Josephson effect and environmental effect can constructively interplay to produce a gain. In the later case, the electromagnetic field would be amplified by the CPB medium, indicating energy conversion from the environment to coherent fields mediated by CPBs.