Available student project - Nanowire DFB lasers

Research fields

  • Photonics, Lasers and Nonlinear Optics
  • Nanoscience and Nanotechnology
Artist's impression of 3 dimensional device integration with nanowires (left) and an optical image of a nanowire laser (right)

Project details

Information processing speed is currently limited by the speed of electronic components on a chip. High density photonic chips are promising for surpassing this limitation and further enhancing information processing speed. Light generation and manipulation at the nanoscale are critical components of any photonic chip. Ultra-small, low threshold, fast and stable semiconductor lasers are the key to high density integration of devices/components on a photonic chip.

Semiconductor nanowires are promising for developing nanoscale lasers. Nanowires are cylindrical semiconductor structures with diameters of few 10s of nm and height/length of few microns. These nanowires thus reduce the foot print of semiconductor devices and also enable 3D device architectures (Figure 1).

This project involves design and demonstration of semiconductor nanowire lasers (Figure 2). Control on the direction of light emission from the nanowire laser gives additional degree of freedom for design of high density photonic chips. This can be achieved by controlling the shape of the nanowires to introduce periodic variations in the refractive index along the length of the nanowire. The periodic variation in the refractive index of the nanowire provides distributed feedback (DFB) and the direction of light emission can be controlled by controlling the periodicity of the index variation.

This project will ultimately lead to faster and more economical/environmentally friendly/low consumption information processing systems.

This project can be divided into the following smaller modules, and students may take up one or more of the following tasks to suit their interests:

  1. Development of analytical and numerical modelling for understanding the photonic behaviour of semiconductor nanowires: This step identifies the exact dimensions of the nanowire to achieve lasing and control the emission direction with respect to the nanowire axis. This step is most suitable for students with aptitude for analytical modelling techniques.

  2. Fabrication of nanowires with periodic index variations along the length: This step involves working with nano-fabrication equipment like FIB (focussed ion beam) and EBL (electron beam lithography) to manipulate the nanowires. This step is most suitable for students aiming to get hands-on experience with state-of-the-art experimental equipment.

  3. Optical characterisation of nanowire emission and nanowire lasers: This step involves handling optical set-ups for gaining an insight into the characteristics of nanowire lasers and is most suitable for students interested in spectroscopic techniques.

Project suitability

This research project can be tailored to suit students of the following type(s)
  • 3rd year special project
  • PhB (1st year)
  • PhB (2nd or 3rd year)
  • Honours project
  • Phd or Masters

Contact supervisor

Tan, Hoe profile
Head of Department

Other supervisor(s)

Jagadish AC, Chennupati profile
Distinguished Professor

Updated:  17 August 2017/ Responsible Officer:  Director, RSPE/ Page Contact:  Physics Webmaster