Circular Polarization Discrimination Enhanced by Anisotropic Media

Abstract

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adom.201901800.Circularly polarized light (CPL) has its electric field rotating with a constant magnitude in a plane perpendicular to the direction of the wave. Based on the direction of rotation, a circularly polarized wave is either left-circularly polarized (LCP) or right-circularly polarized (RCP), corresponding to the two spin states of photons. Owing to the superior robustness of circular polarization states during transmission, [1] during asymmetrical interaction with chiral matters, [2] and in the quantum information carried by its photon spin states, [3] circularly polarized light has promising applications in optical communication, [4] imaging, [5] sensing, [6] and quantum information processing. [7][8][9] Adv. Optical

Integrated Photonic Structure Enhanced Infrared Photodetectors

“…If the integrated photonic structure is carefully designed so that the local field polarization matches the main absorption axis of the active material, the absorptance of the active material can be efficiently enhanced. [ 42,125,126 ] Furthermore, since the photonic structure and the active material are both polarization selective, the device polarization can be significantly enhanced once the double polarization selection is in operation. We will summarize the related work, as follows.…”

“…The device structures are shown in Figure a,b. [ 126 ] As shown in Figure 12c, the CPER of the QW absorptance is close to 14 at the wavelength around 12 μm, whereas the CPER of the MCT absorptance is less than 1.3. [ 126 ] The big contrast between the QWs and the MCT clearly shows that the double polarization selection from the photonic structure and the anisotropic active material can lead to higher CPERs.…”

“…[ 126 ] As shown in Figure 12c, the CPER of the QW absorptance is close to 14 at the wavelength around 12 μm, whereas the CPER of the MCT absorptance is less than 1.3. [ 126 ] The big contrast between the QWs and the MCT clearly shows that the double polarization selection from the photonic structure and the anisotropic active material can lead to higher CPERs. Except the common GaAs/AlGaAs QW, other anisotropic infrared absorption materials, such as InAsSb nanowires, CNT, and some monolayer 2D materials, present well application potential in the field of infrared detection.…”

“…As shown in Figure 12f, at the operating wavelength of 5 μm, the CPER of the device based on the InAsSb nanowire array (anisotropic) is 12.6, which is seven times higher than that of the device based on the InAsSb film (isotropic). [ 126 ] In comparison, the CPERs of the active material absorptance of the photonic structure empowered circular polarization infrared detectors are theoretically lower than 2.5 [ 127 ] and experimentally lower than 2. [ 128–130 ] Therefore, the double polarization selection is demonstrated to be a promising way to achieved circular polarization infrared detectors with high CPER.…”

Building Supramolecular Chirality in Organic Solar Cells Enables High-Performing Circularly Polarized Light Detection

“…As such, direct CPL detection has greatly progressed by using electronic devices based on active materials with intrinsic chirality. These materials include organic conjugated small molecules and polymers 11,12,16,21 , hybrid organic-inorganic perovskite materials 14,15,18 and plasmonic metamaterials 22,23 . Among these materials, the potential of organic conjugated molecules has attracted great attentions in promoting the advancement of chiral optoelectronics, including e cient CPL detection and beyond.…”