August 2016 Vol. 14 No. 8

Front-line Researchers

• Akira Fujiwara, Senior Distinguished Researcher, NTT Basic Research Laboratories

  

  Overview
  Semiconductor technology―the backbone of information and communication technology―has made amazing progress over the years, and more recently, attention has come to focus on the ultimate-level control of single electrons and single atoms using nanofabrication and crystal-growth techniques. What kind of breakthroughs can we expect from NTT’s research on ultimate electronics? We asked Dr. Akira Fujiwara, Senior Distinguished Researcher at NTT Basic Research Laboratories, to update us on recent research achievements and to tell us about his life as a researcher.

Feature Articles: Forefront Research on Bio-soft Materials

• Overview of Bio-soft Material Research at NTT

  

  Abstract
  At NTT Basic Research Laboratories, we are aiming to create a novel nanobiointerface that allows direct access to the human body and brain by utilizing the functions and structures of biomolecules and soft materials. We are also attempting to understand the fundamental principles of bioinformation processing by managing the combination of nanotechnology and biotechnology. The Feature Articles in this issue introduce our bio-soft material research in relation to the fabrication of nanobiodevices, which constitute one of the components of a future artificial synapse. We also present a highly sensitive and long-term stable biosensing system.

• Fabrication of Nanobiodevices that Utilize the Function of Membrane Proteins

  

  Abstract
  Membrane proteins play vital roles in a wide variety of functions in living organisms. The development of nanobiodevices that fuse semiconductor nanotechnology and membrane proteins makes it possible to understand various biological processes as well as engineering applications. In this article, we introduce the fabrication of nanobiodevices that are functionalized by membrane proteins and designed to mimic the synaptic signal transmission mechanism in the nervous system.

• Pattern Formation of Supported Lipid Bilayer for Molecular Manipulation

  

  Abstract
  A supported lipid bilayer (SLB) is an artificial membrane formed on a solid support. We have developed an original technique for controlling the position of an SLB using a pattern fabricated on a solid surface. In this article, I report on two new results obtained using our technique; one involves the use of an SLB microarray for protein detection and the other a molecular gate device that can control a few individual molecules within an SLB.

• Neuronal Growth on Artificial Structures with Different Materials

  

  Abstract
  Neuronal guidance on a device is a key issue to achieve artificial synapses towards the goal of developing artificial post-synaptic structures. NTT Basic Research Laboratories has established a method for examining the in vitro affinity of neurons to a substrate by observing in detail the interface between a neuron and a substrate surface using a focused ion beam/scanning electron microscope at the single neuron level. With this knowledge in hand, we fabricated nanostructures using materials with a high affinity to neurons and examined the ability to control neuronal growth on the structure. We demonstrated the possibility of achieving neuronal guidance on a nanopillar substrate of amorphous silicon, which solves one of several difficulties related to the realization of artificial synapses.

• Time-lapse Imaging of Neural Morphological Changes Relating to Cellular Functions

  

  Abstract
  The human body is composed of trillions of cells. The association between the cells with specialized functions is important in the formation of the skeleton and organs, whose integration is vital for human activity. The nervous system plays a central role in effectively integrating the functions of the skeleton and organs. Here, we introduce research aimed at understanding the relationship between neural function and morphology in the early stages of apoptosis, which plays an important role in the process of neural network formation.

• On-chip Graphene Biosensor

  

  Abstract
  This article describes our recent research on an on-chip biosensor that uses the surface of graphene, an atomically thin carbon sheet modified with specific DNA (deoxyribonucleic acid) molecules, which binds selectively to a target molecule. Biologically important proteins such as cancer markers can be detected simply by adding a sample solution smaller than 1 microliter to the sensor chip. Quantitative detection of multiple proteins on a single graphene biosensor chip is demonstrated by using a microchannel configuration. Our findings have the potential to lead to a simple assay technique for disease markers.

• Conductive Composite Material for Vital Data Measurement

  

  Abstract
  As the interest in healthcare has grown in recent years, the technologies needed to monitor vital data have been attracting a lot of attention with a view to disease diagnosis and prevention as well as lifestyle improvement. At NTT Basic Research Laboratories, we are working on the research and development of conductive composite materials by coating or mixing conductive polymer with biocompatible substrates. We utilize these materials as electrodes for measuring biological signals from, for example, the skin or the heart, with high biocompatibility and sensitivity. We report here on composite electrodes made of conductive polymer (PEDOT:PSS) and silk substrates that are used when measuring biomedical signals via human tissue.

Regular Articles

• Substrate-transfer Technique Using h-BN for GaN-based High-power Transistors

  

  Abstract
  We transferred AlGaN/GaN (aluminum gallium nitride/gallium nitride) high electron mobility transistors from a sapphire substrate to a material with high thermal conductivity using a substrate transfer technique that involves the use of an h-BN (hexagonal boron nitride) release layer. We succeeded in suppressing the self-heating effect and obtained good power performance in direct current characteristics. The transfer technique can overcome thermal problems in power transistors.

• Path Accommodation Design Engine for Simply and Reliably Designing Multi-layer Transport Networks

  

  Abstract
  Core and metro transport networks continue to be simplified with the adoption of 100-Gbit/s packet transport systems. In line with this, the engineering work involved in path accommodation design and management is being carried out as a smooth flow, which is referred to as creating a flow-through operation. This article describes a multi-layer transport path accommodation design engine that takes into account the reliability demanded by each service in order to accommodate optical and multi-granular electrical paths from a few megabits per second to 100 Gbit/s.

Global Standardization Activities

• Trajectory of ITU-T Standardization and Key Issues at the ITU-T CJK CTO Meeting

  

  Abstract
  The ITU-T (International Telecommunication Union - Telecommunication Standardization Sector) CTO (chief technology officer) meeting for the CJK (China, Japan, and Korea) region was held in Seoul, Korea, on March 21, 2016. This article presents the main subjects of discussion at the meeting, namely, 5G (fifth-generation mobile communications system), IoT (Internet of Things), video, and other areas.

Practical Field Information about Telecommunication Technologies

• Recent Case Study of Fault in IP Phone User System

  

  Abstract
  This article describes a problem a customer was having with disconnects in inter-office calling using IP-VPN (Internet protocol virtual private network) services and how we rectified it. This is the thirty-sixth article in a series on telecommunication technologies. This month’s contribution is from the Network Interface Engineering Group, Technical Assistance and Support Center, Maintenance and Service Operations Department, Network Business Headquarters, NTT EAST.

External Awards/Papers Published in Technical Journals and Conference Proceedings

• External Awards/Papers Published in Technical Journals and Conference Proceedings