We show that electromagnetically-induced transparency and lasing without inversion are simultaneously achieved for microwave fields by using a fluxonium superconducting circuit. As a result of the Δ energy-level structure of this artificial three-level atom, we find the surprising phenomenon that the electromagnetically-induced transparency window in the frequency domain is sandwiched between absorption on one side and amplification on the other side.
@article{arxiv.1004.1817,
title = {Electromagnetically-induced transparency with amplification in superconducting circuits},
author = {Jaewoo Joo and Jerome Bourassa and Alexandre Blais and Barry C. Sanders},
journal= {arXiv preprint arXiv:1004.1817},
year = {2010}
}