title: Ultrafast all-optical switching with low saturation energy via intersubband transitions in GaN/AlN quantum-well waveguides.
abstract: A fiber-optic pump-probe setup is used to demonstrate all-optical switching based on intersubband cross-absorption modulation in GaN/AlN quantum-well waveguides, with record low values of the required control pulse energy. In particular, a signal modulation depth of 10 dB is obtained with control pulse energies as small as 38 pJ. Such low power requirements for this class of materials are mainly ascribed to an optimized design of the waveguide structure. At the same time, the intersubband absorption fully recovers from the control-pulse-induced saturation on a picosecond time scale, so that these nonlinear waveguide devices are suitable for all-optical switching at bit rates of several hundred Gb/s.
authors: Department of Electrical and Computer Engineering and Photonics Center, Boston University, Boston, MA 02215, USA.
authors: Yan
authors: Y
authors: Li
authors: Anirban
authors: A
authors: Bhattacharyya
authors: Christos
authors: C
authors: Thomidis
authors: Theodore D
authors: TD
authors: Moustakas
authors: Roberto
authors: R
authors: Paiella
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry*; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005708:Gallium / Q000737:chemistry*; D054023:Lasers, Semiconductor; D012031:Refractometry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*
chemical_list: D017607:Aluminum Compounds; C473348:gallium nitride; C052045:aluminum nitride; D005708:Gallium