Department of Laser and Optical Engineering, University of Bonab, Bonab, Iran.
Faculty of Physics, University of Tabriz, Tabriz, Iran.
Sci Rep. 2020 Oct 14;10(1):17176. doi: 10.1038/s41598-020-74212-8.
We consider a four-level molecular system with two ground-state vibrational levels and two excited-state vibrational levels inside a constant cavity configuration. We discuss the reflected and transmitted Goos-Hänchen (GH) shifts of a positive and negative single-chirped laser pulse. The impacts of the laser field detuning, intensity of applied laser field, and appropriately tuning the chirp rate on GH shifts are then analyzed. It is also found that this sensor is very sensitive to the refractive index of the intracavity medium, which can coherently be controlled by the medium parameters. The results show that such a sensor can be most effective for detecting biological molecules with low concentration than the large number density, where a bit variation in the concentration of sample will lead to a great variation on the GH shifts.
我们考虑了一个具有两个基态振动能级和两个激发态振动能级的四级分子系统，处于恒定腔配置中。我们讨论了正、负单啁啾激光脉冲的反射和透射古斯-汉欣（GH）位移。然后分析了激光场失谐、外加激光场强度以及适当调整啁啾率对 GH 位移的影响。还发现，这种传感器对腔内介质的折射率非常敏感，而腔内介质的折射率可以通过介质参数进行相干控制。结果表明，与高密度相比，这种传感器对于低浓度的生物分子的检测更为有效，因为样品浓度的微小变化将导致 GH 位移的巨大变化。
