- Date:
- 2009-2011
- Theme:
- Nanophotonics and Biomimetics
- Funding:
- EPSRC
Efficient visible (i.e. Red, Green and Blue) laser emissions are desirable for many applications such as optical data storage, reprographics, RGB colour displays, submarine communications, spectroscopy and biotechnology. These applications would benefit from an inexpensive, low noise, good beam quality and highly stable laser source. There are many different methods in which to achieve a visible laser source, these include nonlinear frequency conversion of high powered lasers, the relatively new process of upconversion and semiconductor lasers using a choice of materials for the blue/green spectrum.
By using standard microfabrication techniques, we propose to fabricate compact, mass-producible, high power, high efficiency visible wavelength lasers based on an upconversion process. An upconversion laser operates on the same principle as ordinary lasers. However, the difference comes with the pumping process. The energy from two or more pump photons is combined to excite the already excited atom to a much higher laser level leading to a shorter lasing wavelength than the pump wavelength when it relaxes to the lower energy level.
However, upconversion lasers require a host with a low phonon energy, otherwise multi-phonon transitions reduce the lifetime of the metastable levels making lasing impossible. Therefore, the objectives of our research are:
ââ¬Â¢ To identify a suitable low phonon host, ââ¬Â¢ Co-dope the host with rare-earth ions: Erbium and Ytterbium, ââ¬Â¢ Fabricate a low loss planar ridge waveguide using the co-doped host material and produce an efficient green laser source.
Once successful, we will further our research using different rare earths to achieve a range of visible laser sources.
Primary investigator
Secondary investigators
- sp3
- Martin Charlton
- Prof. James Wilkinson
Associated research groups
- Nano Research Group
- Optoelectronics Research Centre
- Southampton Nanofabrication Centre
- Date:
- 2001-2010
- Themes:
- Nanoelectronics, Energy Harvesting
- Funding:
- EPSRC
As part of the UK Supergen consortium we are currently performing research into methods of enhancing the performance of silicon based thin film solar cells deposited using PECVD. We intend to achieve this primarily through enhancements in the optical absorption of materials by optimisation of cell design and the inclusion of third generation design features such as plasmonics and intermediate reflecting layers.
Thin film cells are created using an Oxford Instruments SYS100 PECVD reactor which is installed in the department's new cleanroom facility. This reactor provides the the ability to deposit silicon, silicon carbide, and silicon germanium in the amorphous or micro crystalline regime providing the potential to investigate many advanced cell designs and configurations.
Deposited cells are typically characterised using techniques such as spectroscopic ellipsometry, AFM, SEM, QE and IQE measurements, and IV characteristic analysis which are all available in house.
Primary investigators
- Darren Bagnall
- odc04r
Secondary investigators
- mar09r
- mb07r
- pjs05r
- fd07r
Partner
- Pilkington Glass
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Themes:
- Microfluidics and Lab-on-a-chip, Bionanotechnology and Biosensors
- Funding:
- Self funded
We developed a new method for formation of artificial bilayer lipid membranes (BLMs) by the controlled, electrical manipulation of aqueous droplets immersed in a lipid-alkane solution. Droplet movement was generated using dielectrophoresis on planar microelectrodes covered in a thin insulator. Droplets, surrounded by lipid monolayers, were brought into contact and spontaneously formed a BLM. The method produced BLMs suitable for acquisition of electrophysiological data from membrane proteins, and the technique can be extended to create programmable BLM arrays and networks.
Primary investigators
- sa05r
- Hywel Morgan
- Nicolas Green
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Theme:
- Nanophotonics and Biomimetics
- Funding:
- Adventure in Research Grant
Current integrated nano-systems are inflexible due to bulky interfaces, with discrete circuit blocks thus robbing the system of portability. In this research, I propose a nano-device that could be applied to different research disciplines through performing sub task. This would be an extremely attractive concept, as it would enhance the adoption of new nanotechnologies by industry. This system will be small and readily portable and could be used in the field as well as in the laboratory for analysis purposes. This research proposal is aimed at a proof-of-concept study of utilising a novel nano resonant cavity based on photonic crystal and photonic wire technology that will eventually evolve into a monolithic nanoscale integrated ââ¬Ëplug-and-playââ¬â¢ component for a variety of interdisciplinary systems. Applications would include bio-environmental-sensing, optical chip interconnects for a multidimensional nanophotonic-electronic integrated circuit board, light extraction unit, photon-assisted bio-medicine and imaging.
Primary investigator
- Harold M H Chong
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Date:
- 2008-
- Theme:
- Microfluidics and Lab-on-a-chip
- Funding:
- EPSRC
As the oceans play a crucial role in the future of our civilization (natural resource, climate regulationââ¬Â¦), it is important to build very accurate model to predict their evolution. One important part of this model is to know our impact on the environment such as the pollution which can be assessed by knowing the different populations of phytoplankton or algae at different depths. Currently the only solution available on a large scale is to obtain water samples for laboratory analysis which induce many issues of cost, contamination, sample degradation, and poor sample frequency in both space and time. However, if an integrated and small flow cytometer system could be realized, platforms such as Argo floats, AUVs (autonomous underwater vehicle) or gliders could be used to bring the system at different depths and to obtain in-situ measurements. Thus, this part of the project has as an aim to develop an integrated flow-cytometer on chip for in situ particle counting and sampling. The targeted species are phytoplankton with a size in the 2 to 50 õm range. The detection of the different species is realized by measuring the fluorescence and the scattered light of the particles when they are illuminated by a laser in the visible wavelength range. As each particle can have different fluorescence properties and as the scattered light is proportionnal to the size (for small angle) and to the granularity/shape of the particles (big angle), we are able to distinguish them.
Primary investigators
- Hywel Morgan
- Dr Matt Mowlem
- db4
- rz08r
Partner
- National Oceanography Centre (Sensors group)
Associated research group
- Nano Research Group
This project is to investigate an efficient modelling, fabrication and characterisation technique to realise a multifunctional integrated nanosystems for nanoelectronic and nanophotonic applications. A rigorous numerical modelling approach based on finite difference time domain method will be explored to simulate the semiconductor nanowire structures. Different semiconductor material (e.g. silicon and zinc oxide) will be investigated and assesed for its suitability for light guiding, absorption and non-linear effect for potential slow light application in optical communication and quantum opticical switching. The nanowire structure will be fabricated using bottom-up approach under different growth conditions to achieve the optimum structural and geometrical features. The photonic and electrical nanowire characterisation will be based on near field optical microscopy, broadband laser spectroscopy and dc semiconductor parametric analyser.
Primary investigators
- Ehsan Jaberansary
- Harold M H Chong
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Theme:
- Nanophotonics and Biomimetics
- Funding:
- Adventure in Research Grant
Current integrated nano-systems are inflexible due to bulky interfaces, with discrete circuit blocks thus robbing the system of portability. In this research, I propose a nano-device that could be applied to different research disciplines through performing sub task. This would be an extremely attractive concept, as it would enhance the adoption of new nanotechnologies by industry. This system will be small and readily portable and could be used in the field as well as in the laboratory for analysis purposes. This research proposal is aimed at a proof-of-concept study of utilising a novel nano resonant cavity based on photonic crystal and photonic wire technology that will eventually evolve into a monolithic nanoscale integrated ââ¬Ëplug-and-playââ¬â¢ component for a variety of interdisciplinary systems. Applications would include bio-environmental-sensing, optical chip interconnects for a multidimensional nanophotonic-electronic integrated circuit board, light extraction unit, photon-assisted bio-medicine and imaging.
Primary investigator
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Funding:
- Adventure in Research Grant
Current integrated nano-systems are inflexible due to bulky interfaces, with discrete circuit blocks thus robbing the system of portability. In this research, I propose a nano-device that could be applied to different research disciplines through performing sub task. This would be an extremely attractive concept, as it would enhance the adoption of new nanotechnologies by industry. This system will be small and readily portable and could be used in the field as well as in the laboratory for analysis purposes. This research proposal is aimed at a proof-of-concept study of utilising a novel nano resonant cavity based on photonic crystal and photonic wire technology that will eventually evolve into a monolithic nanoscale integrated ââ¬Ëplug-and-playââ¬â¢ component for a variety of interdisciplinary systems. Applications would include bio-environmental-sensing, optical chip interconnects for a multidimensional nanophotonic-electronic integrated circuit board, light extraction unit, photon-assisted bio-medicine and imaging.
Primary investigator
- Harold M H Chong
- Date:
- 2008-2011
- Theme:
- Microfluidics and Lab-on-a-chip
- Funding:
- ORS
The oceans cover almost 75% of the planet and affect the lives of every plant and animal on earth. With global climate changing rapidly, the importance of studying the oceans has increased dramatically since they play a crucial role in global climate regulation. A Conductivity, Temperature, Depth (CTD) sensor is the primary tool for determining the physical properties of sea water. This project will present a conductivity sensor based on a 7-electrode cell, and a temperature sensor based on a platinum resistor bridge. Whilst, an impendence measurement system will also be present for collecting and storing the data form the CT sensor.
Primary investigators
- Hywel Morgan
- Dr. Matt Mowlem
Secondary investigator
- xh08r
Associated research group
- Nano Research Group
- Date:
- 2006-2009
- Theme:
- System design and RF
- Funding:
- Department
In this project, the spectrum monitor for cognitive radio is explored. The main challenge of the cognitive radio application is to draw a spectrum map covering a wide range of frequency fast and accurate enough while consuming lower power and keeping lower cost compared with main transceiver circuits, hence a unique receiver (spectrum monitor) must be designed. In this project, the target frequency range covers from 2GHz to 5GHz, which is a potential band for the cognitive radio, and the sensitivity/frequency resolution is to set to -80dBm/200kHz for strong signal detection of most communication systems.
To design such a RF system from system level, a novel method involving the concept of figure of merit is adopted to find a proper solution to balance different aspects of the receiver, including the performance, the power and the cost. By analysing the theory and the statistics collection for key blocks in RF system through years, this method can provide a general guide of trade-off between the power consumption and performance of receiver for the following several years and the trade-off among the performance.
Because of its unique application, some of the key blocks of the spectrum monitor are different from those in popular receivers. the low cost and high integration requirement prompt the design of a lumped element on chip passive band pass filter for IF selection. And a ring oscillator based digital tuning integer frequency synthesizer is designed to fulfill the wide tunig range and the low cost specifications. These components are designed on the 130nm standard digital CMOS technology to keep the lowest cost for portable devices.
The entire spectrum monitor system design involves the specially designed blocks(PLL, BPF) in circuit level simulations, fabrication and measurements as well as the collected existing blocks(such as wideband LNA, high linearity mixer, the base band low pass filter and ADC) since these components are more conventional. The trade-off and evaluation of the receiver solutions will be provided and analyzed.
Primary investigator
Associated research group
- Nano Research Group