BibTex format
@article{Shammah:2014:10.1103/PhysRevB.89.235309,
author = {Shammah, N and Phillips, CC and De, Liberato S},
doi = {10.1103/PhysRevB.89.235309},
journal = {PHYSICAL REVIEW B},
title = {Terahertz emission from ac Stark-split asymmetric intersubband transitions},
url = {http://dx.doi.org/10.1103/PhysRevB.89.235309},
volume = {89},
year = {2014}
}