We study the time evolution of two electron spin states in a double quantum-dot system, which includes a nearby quantum point contact (QPC) as a measurement device. We obtain that the QPC measurement induced decoherence is in time scales of microsecond. We also find that the enhanced QPC measurement will trap the system in its initial spin states, which is consistent with quantum Zeno effect.
@article{arxiv.0808.0550,
title = {Effect of Quantum Point Contact Measurement on Electron Spin State in Quantum Dot},
author = {Fei-Yun Zhu and Zhi-Cheng Zhu and Tao Tu and Hua Tu and Guang-Can Guo and Guo-Ping Guo},
journal= {arXiv preprint arXiv:0808.0550},
year = {2015}
}