A Spectrally Tunable Plasmonic Photosensor with an Ultrathin Semiconductor Region

Abstract

Surface plasmon resonance (SPR) has been widely utilized to improve the absorption performance in the photosensors. Graphene has emerged as a promising plasmonic material, which supports tunable SPR and shows significant flexibility over metals. In this letter, a hybrid photosensor based on the integration of periodic cross-shaped graphene arrays with an ultrathin light-absorbing semiconductor is proposed. A tenfold absorption enhancement over a large range of the incidence angle for both light polarizations as well as a considerably high photogeneration rate (∼ 10 37 ) is demonstrated at the resonance. Compared with traditional metal-based plasmon-enhanced photosensors, the absorption enhancement here can be expediently tuned with manipulating the Fermi energy of graphene. The proposed photosensor can amplify the photoresponse to the incidence light at the selected wavelength and thus be utilized in photosensing with high efficiency and tunable spectral selectivity in the mid-infrared (mid-IR) and terahertz (THz) regime.

Numerical Study of Angle-Insensitive and Tunable Dual-Band THz Absorber Using Periodic Cross-Shaped Graphene Arrays

“…As can be seen in Figure 7, the absorption response of graphene is robust to the variation of the incident angle for both the TE and TM polarizations. As shown in Figure 7a, as θ c is increased from 0° to 40°, the peak absorption of the two absorption bands is still larger than 48.8%, which is comparable to many graphene-based THz selective absorbers [12,13,14,15,16,17,18,19,20,21,29]. In particular, as shown in Figure 7b, the peak absorption of the absorption bands for the TM polarization can be further improved as θ c is increased, and perfect light absorption of graphene with A = 99.4% can be achieved as θ c = 60°.…”

“…Various groups have been working on graphene-based absorbers in the THz region. Many of these absorbers are based on periodically patterned graphene, like disks [11,12], microrings [13], nanoribbons [14,15], elliptical arrays [16,17], cross-shaped [18,19], H-shaped [20] and dumbbell-shaped [21] structures. However, most of these graphene-based absorbers have only one absorption band, and their absorption efficiency is relatively low.…”

Research on Accuracy Analysis and Motion Control of Two-axis Non-magnetic Turntable Based on Ultrasonic Motor Journal

“…In 1954, the turret developed by the Massachusetts Institute of Technology used photoelectric angle-measuring sensors and precision bearings, which improved the precision greatly and hence was put into production [5,6]. At present, the domestic and international turntables have high precision and fast response, providing high calibration accuracy and accurate performance detection for the calibration and testing of inertial navigation components [7,8].…”

Plasmonic absorption characteristics based on dumbbell-shaped graphene metamaterial arrays

“…Graphene SPs both in theory and experiment have attracted great interest. Recently, many articles have proposed a very diverse array of graphene, such as graphene strips, disks, rings and cross structures [18][19][20][21][22]. Plasmonic metamaterial structures have been very attractive in recent years due to their unique active tunability [23,24].…”