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ABSTRACT: We investigated a selective assembly method of fabricating single-walled carbon nanotubes (SWCNTs) on a silicon-dioxide (SiO2) surface by using only a photolithographic process; then, we fabricated 8 x 8 field-emission transistor (FET) arrays for sensor applications. Photoresist (PR) patterns were made on a SiO2-grown Si substrate by using the photolithographic process. This PR-patterned substrate was dipped into a SWCNT solution dispersed in dichlorobenzene (DCB). The PR patterns were removed by using acetone. As a result, selectively-assembled SWCNT channels in 8 x 8 FET arrays could be fabricated between source and drain electrodes without complicated chemical steps using octadecyltrichlorosilane (OTS). Finally, we successfully fabricated 8 x 8 SWCNT-based multi-channel FET arrays by using our novel self-assembly method.
Journal of Nanoscience and Nanotechnology 02/2012; 12(2):1251-5. · 1.56 Impact Factor
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Microelectronics Journal. 01/2008; 39:526-528.
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ABSTRACT: The single mode GaAs/AlGaAs P-p-n-N ridge waveguide phase modulators have been fabricated and the phase shifts have been measured by using a Mach-Zehnder interferometer. The wavelength dependence of the phase modulators is reported between 1.06 mum and 1.55 mum.
Lasers and Electro-Optics - Pacific Rim, 2007. CLEO/Pacific Rim 2007. Conference on; 10/2007
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ABSTRACT: We describe studies of implantation-enhanced quantum-well intermixing in a lattice-matched InGaAs/InGaAsP multiple quantum well p-i-n heterostructure. Samples were implanted with a dose of 5×1014 P+ ions /cm2 at high energy of 1 MeV. The band gap for the samples was determined from photoluminescence at room temperature. The maximum blue-shift of the band gap was 107 nm after the RTA process at 675 °C for 9 minutes. However, it was improved to 140 nm after two-step anneals. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
physica status solidi (c) 04/2007; 4(5):1739 - 1742.
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ABSTRACT: We fabricated photonic crystal structure on GaAs substrate using nanoporous alumina mask. Uniform arrays of nano-sized pores produced in anodic alumina were transferred into GaAs substrate by inductively coupled plasma reactive ion etching (ICP-RIE). The photonic crystal structure, the nanohole array with uniform diameter of 60 nm and interpore distance of 105 nm, was formed on GaAs substrate as replica of the alumina mask. Its photoluminescence (PL) showed enhanced intensity compared with that from GaAs substrate without its structure. The ICP-RIE technique using nanoporous alumina mask can be used as a prospective method in the fabrication of nano-devices for nanotechnology.
Nanotechnology Materials and Devices Conference, 2006. NMDC 2006. IEEE; 11/2006
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ABSTRACT: An all-optical circular shift register based on semiconductor optical amplifiers (SOAs) is experimentally realized. Left bit shifting is performed for three times, in which a single stage consists of two SOAs.
Photonics in Switching, 2006. PS '06. International Conference on; 11/2006
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ABSTRACT: By using the gain nonlinearity characteristics of semiconductor optical amplifier, an all-optical binary half adder at 10 Gbps is demonstrated. The half adder operates in a single mechanism, which is cross gain modulation. The half adder utilizes two logic functions of SUM and CARRY, which can be demonstrated by using XOR and AND gates, respectively. The extinction ratios of both XOR and AND gates are about 6.1 dB. By achieving this experiment, we also explored the possibilities for the enhanced complex logic operation and higher chances for multiple logic integration.
Optics Express 11/2006; 14(22):10693-8. · 3.59 Impact Factor
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ABSTRACT: We simulated and demonstrated all-optical multi-functional logic gates for simultaneous operations at 10 Gbps. All-optical XNOR, NOR and AND operations are simultaneously realized in this work.
Optical Internet and Next Generation Network, 2006. COIN-NGNCON 2006. The Joint International Conference on; 08/2006
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ABSTRACT: Ion implantation-induced quantum well intermixing (QWI) of InGaAs/InGaAsP quantum well structure has shown to be an efficient way to fabricate photonic integrated circuits. We investigate the characteristics of a newly developed QWI with two-step thermal treatments.
Optical Internet and Next Generation Network, 2006. COIN-NGNCON 2006. The Joint International Conference on; 08/2006
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ABSTRACT: By using cross-gain modulation of a semiconductor optical amplifier, a high-speed all-optical OR logic gate has been proposed and demonstrated with a single semiconductor optical amplifier at 10 Gbit/s.
Lasers and Electro-Optics Society, 2005. LEOS 2005. The 18th Annual Meeting of the IEEE; 11/2005
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ABSTRACT: This study demonstrates the lasing characteristics of InGaAs/InGaAsP multiple-quantum-well waveguide-type depleted optical thyristor using the vertical window. The measured switching voltage and current are 3.36 V and 10 μA, respectively. The lasing threshold current is 131 mA at 25 °C. The output peak wavelength is 1570 nm at a bias current of 1.22 Ith and there is no input signal. The vertically injected depleted optical thyristor shows very good isolation between input and output signals.
Applied Physics Letters 01/2005; 86(2):021108-021108-3. · 3.84 Impact Factor
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ABSTRACT: We have demonstrated a broad-band all-optical flip-flop for wavelength-division-multiplexing system based on optical bistability in a semiconductor optical amplifier (SOA)/distributed feedback (DFB)-SOA with wide gain bandwidth for both SOA and DFB-SOA regions. Input signal with two different wavelength selections of 1530.45 and 1578.12 nm and the repetition ration of about 6 ns is injected into the SOA/DFB-SOA.
IEEE Photonics Technology Letters 03/2004; · 2.19 Impact Factor
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ABSTRACT: By using the cross-gain modulation of semiconductor optical amplifiers
(SOAs), a novel all-optical AND gate has been successfully demonstrated
at 10 Gb/s. Firstly, Boolean \overline{B} was obtained using the first
SOA with signal B and clock injection. Then, the all-optical AND gate is
achieved by simultaneously injecting signal A and signal \overline{B}
out of the first SOA.
Japanese Journal of Applied Physics 01/2004; 43:608. · 1.06 Impact Factor
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Numerical Simulation of Semiconductor Optoelectronic Devices, 2003. NUSOD 2003. Proceedings of the IEEE/LEOS 3rd International Conference on; 02/2003
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ABSTRACT: We present a demonstration of a waveguide-type depleted optical thyristor laser diode with InGaAs/InGaAsP multiple-quantum-well structure. The measured switching voltage and current are 4.63 V and 10 μA, respectively. The holding voltage and current are, respectively, 0.59 V and 20 μA. The lasing threshold currents at 25 °C and 10 °C are 111 mA and 72.5 mA, respectively. The lasing wavelength is centered at 1.561 μm at a bias current equal to 1.41 times threshold. © 2003 American Institute of Physics.
Applied Physics Letters 01/2003; 82(2):158-160. · 3.84 Impact Factor
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ABSTRACT: The novel design of an all-optical XOR gate by using cross-gain modulation of semiconductor optical amplifiers has been suggested and demonstrated successfully at 10 Gb/s. Boolean AB~ and A~B of the two input signals A and B have been obtained and combined to achieve the all-optical XOR gate. No additional input beam such as a clock signal or continuous wave light is used in this new design, which is required in other all-optical XOR gates.
IEEE Photonics Technology Letters 11/2002; · 2.19 Impact Factor
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ABSTRACT: We have demonstrated for the first time an all-optical flip-flop based on optical bistability of an integrated SOA/DFB-SOA by applying an input signal with the period of 25.2 ns. An all-optical flip-flop based on optical bistability is expected to process the signal at an ultra-high speed in a light-wave communication. All-optical flip-flop has various applications such as all optical memory, demultiplexing, packet-header buffering, and retiming. Moreover, an integrated SOA/DFBSOA can perform all-optical logic operation and wavelength conversion by cross gain modulation.
Optical Fiber Communication Conference and Exhibit, 2002. OFC 2002; 04/2002
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ABSTRACT: We have stabilized a 10 GHz harmonically mode-locked fiber ring laser by cavity length feedback control over 16 hours. The timing jitter and amplitude noise of the laser were measured from SSB noise spectra of the 1st and 4th harmonics.
Lasers and Electro-Optics Society, 2002. LEOS 2002. The 15th Annual Meeting of the IEEE; 02/2002
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ABSTRACT: To improve the characteristics of optical devices that used be WDM
system optimally, we investigated two types of structures that consisted
to be a non-uniform thickness quantum well. A possibility of the flat
gain in the broad band is presented by optimizing the variation of wells
thickness. This structure has different gain characteristics for
different sequence of the well from p or n side. Thus, gain
characteristics for two types of the structures were calculated to
achieve broad range gain flatness for the non-uniform quantum well
structure, the spontaneous emission also showed broadband
characteristics. They have 3 dB bandwidths of spontaneous emission that
are 57 nm, 50 nm respectively. And 3 dB bandwidths of structures are 1.4
times, 1.3 times wider than conventional structure
Indium Phosphide and Related Materials, 2000. Conference Proceedings. 2000 International Conference on; 02/2000
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ABSTRACT: All-optical logic AND at 20 Gbit/s was demonstrated using an all-optical SOA-based Mach-Zehnder interferometric wavelength converter, by injecting a pulse data stream into probe signal input instead of continuous wave. It is expected that the AOWC can be utilized for full functionality of Boolean logic due to the nonlinear optical properties
Lasers and Electro-Optics Society 2000 Annual Meeting. LEOS 2000. 13th Annual Meeting. IEEE; 02/2000
