Fiber‐Optic Communication Systems

Vertically Illuminated, Resonant Cavity Enhanced, Graphene–Silicon Schottky Photodetectors

“…σ=61-4.3i [µS] includes both contributions from the inter-and intraband transitions [49,50], assuming a SLG doping∼0.25eV and scattering time∼50fs. The simulation indicates that the absorption peaks are spaced by 1.65nm (Fig.2), matching the free-spectral range (FSR) of the F-P cavity [1]:…”

“…Near infrared (NIR) photodetection at 1550nm is of paramount importance for a variety of applications, ranging from optical communications [1][2][3][4] to remote sensing [5,6]. In modern telecom systems, operation at 1550nm benefits from a reduced light absorption in optical fibers [1].…”

“…In modern telecom systems, operation at 1550nm benefits from a reduced light absorption in optical fibers [1]. In free-space optical communications (FSO) [2][3][4] and light-radars (LIDARs) [5,6], this minimizes the propagation losses in fog [3] and humid conditions [4], due to lower optical absorption and scattering compared to wavelengths< 1µm, and improves eye safety because the outer layer of the eye (cornea) absorbs light at 1550nm and does not allow it to focus on the retina [3,5].…”

“…Many photodetectors (PDs) for 1550nm have been proposed [1,[8][9][10]. For telecom and datacom applications, these typically rely on a waveguide configuration [11][12][13][14][15][16][17][18][19][20], in which optical confinement and guiding contribute to enhanced light absorption and photodetection.…”

“…InGaAs, InP) [21,22] and group IV (Ge) [11][12][13][14] semiconductors are the materials of choice for vertically-illuminated NIR PDs, due to their high (>90%) [8] NIR absorption. The ever growing demand and performance requirements in modern systems (such as bit-rate, number of pixels, imaging matrix size, operation and processing speed) [1,8] make it crucial to integrate PDs with supporting circuitry (drivers, amplifiers, processors) on the same chip. Since modern microelectronics relies on mature complementary metal-oxide-semiconductor (CMOS) technology, the development of NIR PDs on Si is promising for integrated microsystems, combining both optical and electronic functionalities.…”