- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
High-Sensitivity Terahertz Refractive Index Sensor in a Multilayered Structure with Graphene
摘要： In this paper, we propose a high‐sensitivity optical sensor at terahertz frequencies based on a composite structure containing a one‐dimensional photonic crystal (1D PC) coated with a layer of monolayer graphene. Between the 1D PC and the graphene there is a sensing medium. This high‐sensitivity phenomenon originates from the excitation of optical resonance between the graphene and the 1D PC. The proposed sensor is highly sensitive to the Fermi energy of graphene, the thickness and refractive index of the sensing medium, and the number of graphene layers. By selecting appropriate parameters, the maximum sensitivity (407.36 / RIU) is obtained. We believe the proposed configuration is promising for fabricating graphene‐based biosensor‐ or gas‐sensor devices and other related applications in the terahertz band.
关键词： optical resonance,terahertz sensor,graphene
更新于2025-09-23 15:19:57
-
Optical resonance near the edge of a photonic band gap (PBG): turning the effects of a PBG on/off using a resonant driving field
摘要： We studied the effects of a coherent monochromatic resonant laser field driving the transition of a two-level atom embedded in a photonic band gap (PBG) material on the emission dynamics of the atom. When the transition frequency of the atom lies outside a PBG and sufficiently far from the band edge that the emission dynamics of the atom is not normally affected by the gap, the dynamic stark splitting of the upper level of the atom into two dressed states by a sufficiently strong resonant driving field can bring the lower dressed state close enough to the band edge or even inside the gap so as to be affected by the gap, providing a switchable means of extending the novel effects of atom–photon interaction near the edge of a PBG for atomic transitions outside the gap and far from the band edge. The net effect is as if a sufficiently strong resonant field driving a transition of an atom embedded in a PBG actively shifts the PBG close enough to the transition so that the gap affects the emission dynamics associated with the transition.
关键词： Photonic band gap,dynamic Stark splitting,optical resonance
更新于2025-09-19 17:15:36
-
Double-Layer Cross-Coupled Silicon Nitride Multi-Ring Resonator Systems
摘要： We demonstrate a double-layer Si3N4 multi-ring resonator system, where an S-bend waveguide is cross-coupled with a ring cavity loaded with two sub-ring resonators. The device performance is analyzed by using the transfer matrix method. The alignment-error-induced device performance variations are also discussed. The measured spectra coincide well with the simulated results. The device has high tuning flexibility and more design freedom with two sub-rings placed above the ring cavity. The spectrum profile can also be tuned by changing the cross-coupling coefficient. A heater placed above the resonator can shift the resonant wavelength effectively.
关键词： Optical resonance,silicon nitride,integrated optics
更新于2025-09-16 10:30:52