Abstract: A method for forming a PN junction in graphene includes: forming a graphene layer, and forming a DNA molecule layer on a partial region of the graphene layer, the DNA molecule layer having a nucleotide sequence structure designed to provide the graphene layer with a predetermined doping property upon adsorption on the graphene layer. The DNA molecule has a nucleotide sequence structure designed for doping of graphene so that doped graphene has a specific semiconductor property. The DNA molecule is coated on the surface of the graphene layer of which the partial region is exposed by micro patterning, and thereby, PN junctions of various structures may be formed by a region coated with the DNA molecule and a non-coated region in the graphene layer.

Abstract: A plasmonic all-optical switch includes a graphene layer, a first dielectric layer located on the graphene layer, a nano-antenna located on the first dielectric layer, and a second dielectric layer located on the nano-antenna. An incident beam is propagated by means of a surface plasmon wave generated at an interface between the graphene layer and the first dielectric layer. Further, localized surface plasmon resonance is selectively generated at an interface between the nano-antenna and the second dielectric layer by means of a pump beam incident to the nano-antenna to decrease an intensity of the incident beam. The plasmonic all-optical switch may operate at an ultrahigh speed just with a small light energy without any electric method, greatly reduce power consumption of an IT device by applying to an all-optical transistor or the like, and increase a processing rate.

Abstract: A plasmonic all-optical switch includes a graphene layer, a first dielectric layer located on the graphene layer, a nano-antenna located on the first dielectric layer, and a second dielectric layer located on the nano-antenna. An incident beam is propagated by means of a surface plasmon wave generated at an interface between the graphene layer and the first dielectric layer. Further, localized surface plasmon resonance is selectively generated at an interface between the nano-antenna and the second dielectric layer by means of a pump beam incident to the nano-antenna to decrease an intensity of the incident beam. The plasmonic all-optical switch may operate at an ultrahigh speed just with a small light energy without any electric method, greatly reduce power consumption of an IT device by applying to an all-optical transistor or the like, and increase a processing rate.

Abstract: A method for forming a PN junction in graphene includes: forming a graphene layer, and forming a DNA molecule layer on a partial region of the graphene layer, the DNA molecule layer having a nucleotide sequence structure designed to provide the graphene layer with a predetermined doping property upon adsorption on the graphene layer. The DNA molecule has a nucleotide sequence structure designed for doping of graphene so that doped graphene has a specific semiconductor property. The DNA molecule is coated on the surface of the graphene layer of which the partial region is exposed by micro patterning, and thereby, PN junctions of various structures may be formed by a region coated with the DNA molecule and a non-coated region in the graphene layer.

Abstract: Disclosed are a device for detecting a single photon available at a room temperature, which includes: a signal transmitting unit including a first electrode and a second electrode spaced apart from each other and at least one nanostructure disposed between the first electrode and the second electrode, the first electrode receiving a signal from the signal generating unit; a photonic crystal lattice structure for receiving a photon, the photonic crystal lattice structure having an optical waveguide for guiding the received photon to the first electrode, the optical waveguide being formed by a plurality of dielectric structures; and a single photon detector for detecting a photon by analyzing a signal output to the second electrode, and a method for detecting a single photon using the device.

Abstract: The present invention relates to an apparatus and a method for realizing all-optical NOR logic device using the gain saturation characteristics of a semiconductor optical amplifier(SOA). More particularly, the invention relates to a 10 Gbit/s all-optical NOR logic device among all-optical logic devices, in which a signal transmitted from a given point of an optical circuit such as an optical computing circuit is used as a pump signal and a probe signal.

Abstract: A fabrication method of an epilayer structure for InGaAsP/InP ridge waveguide phase modulator with high phase modulation efficiency. It relates to a P-p-n-N InGaAsP/InP ridge waveguide phase modulator fabricated to be that the phase change of the TE-mode is linearly proportional to the reverse bias voltage at 1.55 ?m wavelength. A method for fabricating an epilayer structure for achieving the optical confinement in the vertical direction of an InGaAsP/InP waveguide phase modulator, characterized by comprising the steps of: forming a first cladding layer of N-InP on an N+-InP substrate; forming a first waveguide layer of n-InGaAsP and a second waveguide layer of p-InGaAsP in sequence on the first cladding layer; forming a second cladding layer of P-InP and a third cladding layer of P-InP in sequence on the second waveguide layer; and forming an electrode layer of p+InGaAs on the third cladding layer.