mobile | classic  
Dataweek Electronics & Communications Technology Magazine





Follow us on:
Follow us on Facebook Share via Twitter Share via LinkedIn


Search...

Electronics Buyers' Guide

Electronics Manufacturing & Production Handbook 2017


 

Transducer links sound, light and radio waves
18 May 2016, Electronics Technology

Researchers working at the National Institute of Standards and Technology (NIST) in the USA have developed a ‘piezo-optomechanical circuit’ that converts signals among optical, acoustic and radio waves.

A system based on this design could move and store information in next-generation computers.

While Moore’s Law, the idea that the number of transistors on an integrated circuit will double every two years, has proven remarkably resilient, engineers will soon begin to encounter fundamental limits. As transistors shrink, heat and other factors will begin to have magnified effects in circuits. As a result, researchers are increasingly considering designs in which electronic components interface with other physical systems that carry information such as light and sound.

Interfacing these different types of physical systems could circumvent some of the problems of components that rely on just one type of information carrier, if researchers can develop efficient ways of converting signals from one type to another (transduction). For example, light is able to carry a lot of information and typically doesn’t interact with its environment very strongly, so it doesn’t heat up components like electricity does.

As useful as light is, however, it isn’t suited to every situation. Light is difficult to store for long periods, and it can’t interact directly with some components of a circuit. On the other hand, acoustic wave devices are already used in wireless communications technology, where sound is easier to store for long periods in compact structures since it moves much more slowly.

To address such needs, NIST researchers and their collaborators built a piezoelectric optomechanical circuit on a chip. At the heart of this circuit is an optomechanical cavity, which in their case consists of a suspended nanoscale beam. Within the beam are a series of holes that act sort of like a hall of mirrors for light (photons). Photons of a very specific colour or frequency bounce back and forth between these mirrors thousands of times before leaking out. At the same time, the nanoscale beam confines phonons, that is, mechanical vibrations, at a frequency of billions of cycles per second (GHz).

The photons and phonons exchange energy so that vibrations of the beam influence the buildup of photons inside the cavity, while the buildup of photons inside the cavity influences the size of the mechanical vibrations. The strength of this mutual interaction, or coupling, is one of the largest reported for an optomechanical system.

One of the researchers’ main innovations came from joining these cavities with acoustic waveguides, which are components that route sound waves to specific locations. By channelling phonons into the optomechanical device, the group was able to manipulate the motion of the nanoscale beam directly. Because of the energy exchange, the phonons could change the properties of the light trapped in the device.

To generate the sound waves, which were at GHz frequencies, they used piezoelectric materials, which deform when an electric field is applied to them and vice versa. By using a structure known as an ‘interdigitated transducer’ (IDT), which enhances this piezoelectric effect, the group was able to establish a link between radio frequency electromagnetic waves and the acoustic waves. The strong optomechanical links enable them to optically detect this confined coherent acoustic energy down to the level of a fraction of a phonon.

They also observed controllable interference effects in sound waves by pitting electrically and optically generated phonons against each other. According to one of the paper’s co-authors, Kartik Srinivasan, the device might allow detailed studies of these interactions and the development of phononic circuitry that can be modified with photons.

“Future information processing systems may need to incorporate other information carriers, such as photons and phonons, in order to carry out different tasks in an optimal way,” says Srinivasan, a physicist at NIST’s Centre for Nanoscale Science and Technology. “This work presents one platform for transducing information between such different carriers.”

For more information visit www.nist.gov


  Follow us on Facebook Share via Twitter Share via LinkedIn    

Further reading:

  • Wits researchers make breakthrough in quantum electronics
    31 January 2017, This Week's Editor's Pick, News, Electronics Technology
    The group, headed by Professor Somnath Bhattacharyya, has been working for the past 10 years on developing carbon-based nanoelectronic devices.
  • Contactless fingerprint sensing technology developed at CSIR
    9 November 2016, This Week's Editor's Pick, News, Electronics Technology
    The Council for Scientific and Industrial Research (CSIR) has developed a new-generation fingerprinting sensing technology using high-speed, large-volume optical coherence tomography (OCT). The device ...
  • Communication technique developed for implanted medical devices
    5 October 2016, News, Electronics Technology
    Researchers at the University of Washington have devised a method of wireless communication that allows devices such as brain implants, contact lenses, credit cards and smaller wearable electronics to ...
  • Li-metal battery promises double capacity of Li-ion
    5 October 2016, This Week's Editor's Pick, Electronics Technology
    SolidEnergy Systems, a company founded in 2012 by MIT alumnus Qichao Hu, is preparing to commercialise a novel rechargeable lithium metal battery that is said to offer double the energy capacity of the ...
  • Audi researching shock absorbers that harvest energy
    5 October 2016, Electronics Technology
    New technology from Audi aims to ease the pain of driving on rough roads, in more ways than one. The company is working on a prototype called eROT, in which electromechanical rotary dampers replace the ...
  • Breakthrough towards carbon nanotubes succeeding silicon
    10 August 2016, This Week's Editor's Pick, News, Electronics Technology
    Researchers at the Technion-Israel Institute of Technology have developed a method for growing carbon nanotubes that could lead to the day when molecular electronics replace the ubiquitous silicon chip ...
  • New phosphor promises better, cheaper lighting
    10 August 2016, Opto-Electronics, Electronics Technology
    Researchers from KU Leuven, the University of Strasbourg, and CNRS have discovered a new phosphor that could make next-generation fluorescent and LED lighting even cheaper and more efficient. The team ...
  • Research towards limitless Li-ion battery lifetime
    15 June 2016, Power Electronics / Power Management, Electronics Technology
    Researchers cycled the testing electrode up to 200 000 times over three months without detecting any loss of capacity or power, and without fracturing any nanowires.
  • Laser breakthrough made by SA and Italian team
    20 April 2016, News, Electronics Technology
    Nature Photonics recently published research by a team from South Africa and Italy demonstrating a new type of laser that is able to produce laser beams ‘with a twist’ as its output.
  • Memristor pioneer releases new devices plus data for modelling
    24 February 2016, Electronics Technology
    Knowm has released two new variants of its device, as well as raw device data aimed at aiding researchers’ ability to develop and improve memristor models.
  • New dimension discovered to high-temperature superconductivity
    27 January 2016, Electronics Technology
    A team led by scientists at the US Department of Energy’s SLAC National Accelerator Laboratory combined powerful magnetic pulses with some of the brightest X-rays on the planet to discover a surprising ...
  • Non-volatile optical memory chip developed
    27 January 2016, Electronics Technology
    Material scientists from the Karlsruhe Institute of Technology and the Universities of Oxford, Münster and Exeter have developed the world’s first entirely light-based memory chip to store data permanently. ...

 
 
         
Contact:
Technews Publishing (Pty) Ltd
1st Floor, Stabilitas House
265 Kent Ave, Randburg, 2194
South Africa
Publications by Technews
Dataweek Electronics & Communications Technology
Electronic Buyers Guide (EBG)

Hi-Tech Security Solutions
Hi-Tech Security Business Directory

Motion Control in Southern Africa
Motion Control Buyers’ Guide (MCBG)

South African Instrumentation & Control
South African Instrumentation & Control Buyers’ Guide (IBG)
Other
Terms & conditions of use, including privacy policy
PAIA Manual





 

         
    Classic | Mobile

Copyright © Technews Publishing (Pty) Ltd. All rights reserved.