Overview of Research in Laboratories

Material Science Laboratory

Hiroki Hibino

   This laboratory aims at contributing to progress in materials science and revolutionizing information communication technology by creating new materials and functions through materials design at the atomic and molecular levels.
   This laboratory consists of three research groups investigating a wide range of materials such as nitride semiconductors, graphene, superconductors, and biological molecules. We are conducting innovative materials research based on the technologies of growing high-quality thin films and precisely measuring the structure and physical properties of materials.
   This year, we succeeded in measuring extremely narrow violet photoluminescence line from ultrathin InN single quantum well on step-free GaN surface, demonstrating label-free protein detection on graphene oxide surface, and achieving electrocardiography simply by wearing a piece of clothing that has textile electrodes combined with conductive polymer.

Physical Science Laboratory

Akira Fujiwara

   The aim of this laboratory is to develop semiconductor- and superconductor-based solid-state devices, which will have a revolutionary impact on future communication and information technologies. Utilizing high-quality crystal growth techniques and nanolithography techniques we have developed, five research groups are working on nanodevices, quantum information processing devices, and high-sensitivity sensors based on new degrees of freedom such as single electrons, mechanical oscillations, quantum coherent states, and spins.
   This year we succeeded in measuring and controlling the velocity of plasmons in graphene and realizing "cavity-electromechanics" with a nanomechanical resonator, which is a classical analogy of cavity quantum electrodynamics. We also demonstrated the operations of novel devices such as a logic device with an electromechanical membrane resonator and a sensor based on stochastic resonance with silicon nanotransistors.

Optical Science Laboratory

Tetsuomi Sogawa

   This laboratory aims for the development of core-technologies that will innovate on optical communications and optical signal processing, and seeks fundamental scientific progresses.
   The groups in our laboratory are working for the quantum state control by very weak light, the search for intriguing phenomena using very intensive and short pulse light, and control of optical properties by using photonic crystals and ultrasonic techniques, based on unique properties of semiconductor nanostructures such as quantum dots and nanowires.
   In this year, we demonstrated a Bose-Einstein condensate of cold atoms on the superconducting atom chip. We succeeded in generating a polarization entangled photon pair with a high quality by use of an integrated silicon photonic circuit. We also demonstrated that electron spins in semiconductors can be transported and manipulated by using surface acoustic waves and that electron spin resonance can be achieved in the absence of real magnetic fields.

Nanophotonics Center

Masaya Notomi

   Nanophotonics Center (NPC) was just established in April 2012 by several research groups involved with nanophotonics in NTT Basic Research Laboratories, NTT Photonics Laboratories, and NTT Microsystem Integration Laboratories. We are aiming for developing a full-fledged large-scale photonic integration technology by which we will be able to densely integrate a large number of nano-scale photonic devices with various functions in a single chip. Furthermore, we are targeting extreme reduction of the consumption energy for photonic information processing by taking advantage of the nanophotonics technology.
   Currently, we are conducting studies of photonic crystals to reduce the footprint and consumption energy of various photonic devices, such as all-optical switches, all-optical memories, and lasers. We are also studying various photonic nanostructures to ultimately enhance light-matter interactions, and exploiting photonic integrated circuits and devices based on the silicon photonic platform. Furthermore, we are developing ultra-fine nanofabrication technologies based on electron beam lithography and sophisticated integration technologies of active semiconductors for photonics.