Optical Chirality Detection Using a Topological Insulator Transistor

Abstract

of CPL can serve as a molecule-screening tool. In fact, it is widely used in drug screening to discern effective medical target products from ineffective or even toxic enantiomers. [2] The emerging applications in quantum communication and computing, [3,4] circular dichroism spectroscopy, and polarimetric imaging [5] also demand optical chirality detection. However, conventional solutions for optical chirality detection require multiple optical elements including phase retarders, quarter waveplate (QWP), polarizing beam splitters, and rotating optomechanical components. This is due to the lack of intrinsic chiral response in common semiconductors such as silicon and III-V semiconductors from which photodetectors are made, thus, miniaturization of optical chirality detection devices is challenging. One direction of seeking chirality detecting devices is using intrinsically chiral materials including chiral dyes and liquid crystals. The first organic-semiconductor transistor for chirality detection utilized chiral helicene [6] and hybrid perovskite devices were explored by combining the chiral-sensitive absorbing organic material and inorganic compound to enhance the optoelectronic performance. [7,8] The invention of metamaterials or metasurfaces, that is, fabrication of sub-diffraction-limited nanostructures, enabled chiral optical properties beyond those offered by naturally existing materials. Metamaterials with helical nanostructures, for example, spirals that lack mirror symmetry, exhibit chirality-dependent absorption/transmission, and have been shown to achieve direct chirality detection. [9][10][11][12][13][14] Alternatively, metamaterials and metasurfaces also demonstrated the capability of manipulating polarization states, [15] and could function as ultracompact optical elements including linear/circular polarizers, [11] waveplates/ phase-retarders, [16] and polarizing beam splitters. [17] Fabricating these optical elements on top of conventional photodetectors can resolve the optical chirality [18,19] or extract the full Stokes parameters. [20] Topological insulators (TIs) are a new phase of quantum materials with topological surface states (TSS) on the surface. [21,22] Tetradymites are known as one of the best roomtemperature thermoelectric materials for decades [23][24][25][26] and also have been applied in optoelectronics, [27][28][29] and later proven to be 3D TIs. [30][31][32][33] The spin texture of the TSS electrons is locked to their momentum, so that the spin polarization can be induced

Topological Materials for Functional Optoelectronic Devices

“…[64,95,97] Very recently Yang et al have reported a device based on 3D TI Bi 2 Se 3 /MoO 3 with responsivity as high as 1.6 × 10 4 and 2.61 × 10 3 AW −1 at 405 and 1310 nm, respectively (Figure 5h). Recent advances in using TMs such as Bi 2 Te 2 Se for optical chirality detection [102] and type-II TDS PtTe 2 for angle-sensitive detection [103] are promising to open up new directions in this field. Nanophotonic devices harnessing the outstanding optoelectronic properties of TIs, Dirac, and Weyl semimetals, have been mostly developed so far using binary, ternary and quaternary Bi and Sb chalcogenides as material platforms.…”

Ultrafast Interfacial Carrier Dynamics and Persistent Topological Surface States in VSe2/Bi2Se3 Van Der Waals Heterojunctions

“…1,2 The topological surface state with massless Dirac fermions exhibits unique properties of spin-momentum locking ensured by Z2 invariant in three-dimensional (3D) TIs including Bi2Se3. A spin-polarized and defect-tolerant conducting channel of these TIs enables promising electronic, optoelectronic, and spintronic applications, 2,3 such as ultralow-power tunnel transistor, 4,5 opto-spintronics with polarized photocurrent, 6,7 high-performance broadband photodetector, 8,9 and nonvolatile memory by spin-transfer torque. 10 For device applications in transistors or external circuits, contact with metal electrodes plays a crucial role.…”

Ultrafast interfacial carrier dynamics and persistent topological surface states of Bi2Se3 in heterojunctions with VSe2

“…The topological surface state with massless Dirac fermions exhibits unique properties of spin-momentum locking ensured by Z 2 invariant in three-dimensional (3D) TIs including Bi 2 Se 3 . A spinpolarized and defect-tolerant conducting channel of these TIs enables promising electronic, optoelectronic, and spintronic applications 2,3 , such as ultralow-power tunnel transistor 4,5 , optospintronics with polarized photocurrent 6,7 , high-performance broadband photodetector 8,9 , and nonvolatile memory by spintransfer torque 10 . For device applications in transistors or external circuits, contact with metal electrodes plays a crucial role.…”