title: Large aperture asymmetric Fabry Perot modulator based on asymmetric tandem quantum well for low voltage operation.
abstract: Large aperture image modulators used as demodulator in receiver path are an important component for the use in three dimensional (3D) image sensing. For practical applications, low voltage operation and high modulation performance are the key requirements for modulators. Here, we propose an asymmetric Fabry-Perot modulator (AFPM) with asymmetric tandem quantum wells (ATQWs) for 3D image sensing. By using ATQWs for the AFPM design, the device operated at -4.25V, and the operating voltage was significantly lower by about 23% compared to -5.5V of a conventional AFPM with 8nm thick multiple QW with a single QW thickness (SQWs), while achieving high reflectivity modulation in excess of 50%. The performance of the fabricated devices is in good agreement with theoretical calculations. The pixelated device shows a high modulation speed of 21.8 MHz over a large aperture and good uniformity. These results show that AFPM with ATQWs is a good candidate as an optical image modulator for 3D image sensing applications.
authors.affiliation: School of Information and Mechatronics, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712, South Korea.
authors.forename: Byung Hoon
authors.initials: BH
authors.lastname: Na
authors.forename: Gun Wu
authors.initials: GW
authors.lastname: Ju
authors.forename: Hee Ju
authors.initials: HJ
authors.lastname: Choi
authors.forename: Yong Chul
authors.initials: YC
authors.lastname: Cho
authors.forename: Yong Hwa
authors.initials: YH
authors.lastname: Park
authors.forename: Yong Tak
authors.initials: YT
authors.lastname: Lee
mesh_terms: D011211:Electric Power Supplies; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D007368:Interferometry / Q000295:instrumentation*