[原分所] 08/21學術演講訊息-Dr. Yang Hui Ying
截止日期：2012-08-21
Title: Lasers and Light Emitting Diodes Based on Defective Nanowires
Speaker: Dr. Yang Hui Ying (Singapore University of Technology and Design, Singapore)
Time: 2:00-4:00PM, August 21 (Tuesday)
Place: Dr. Poe Lecture Hall, IAMS (原分所浦大邦講堂 臺大校園內)
Contact: Dr. Lain-Jong Li 李連忠博士
Dr. Yang Hui Ying is one of the pioneering batch faculty members of SUTD. Her current research interests and projects include the development of metal oxide and carbon nanomaterials based solid state lighting, water purification membrane and energy storage devices. Since year 2005, Dr. Yang has published more than 78 peer-reviewed articles in many prestigious international journals including Adv. Mater., Adv. Func. Mater., ACS Nano, Small, Appl. Phys. Lett., Nanoscale, and ACS Appl. Mater. Interfaces, which have been cited over 968 times. Dr. Yang was the recipient of the prestigious Lee Kuan Yew Fellowship (2008), Singapore Millennium Foundation Fellowship (2006), L’Oreal Singapore for Women in Science national Fellowship (2010), Chinese Government Award for Outstanding Self-Financed Students Abroad (2005), Second Prize in MRS Science-as-Art Competition (2008), and First Prize in NTU Nanoscience-as-Art Competition (2005). She and her research works have been highlighted by many international and local Medias, such as Discovery Channel, Channel News Asia, Straits times, Wall Street Journals, etc.
【Abstract】
The research and innovation in novel lighting technology based on solid state lighting (i.e., organic and inorganic light emitting diodes (LEDs)) are of central industrial and social relevance. LEDs present many advantages over conventional light bulbs and incandescent light sources, such as lower energy consumption, longer lifetime, improved robustness, smaller size, and greater durability. Semiconductor nanowires with wide bandgap are important materials for the development of transparent diodes and transistors, photovoltaic devices, and liquid crystal displays. Recently, we discovered that the defect states induced inside the surface of nanostructured SnO2 semiconductor supports huge amount of radiative excitonic recombination centres. In contrast to conventional light emitting materials, SnO2 and a group of transparent metal oxide materials (i.e., ITO, In2O3, TiO2, GeO2, Cu2O, CuCrO2, etc) have either dipole-forbidden transition or indirect bandgap which limited the further development of transparent electroluminescent technologies for the upcoming application in transparent display. In addition, weakly bound excitons, which generated inside the surface defect states of SnO2 nanowires, supported intensive ultraviolet stimulated emission via giant-oscillator-strength effect. It is also found that the weakly bound excitons and emission wavelength can be controlled by modifying the surface geometry of the nanostructured semiconductors. This is equivalent to achieve spatial and quantum confinement of excitons into nanoscale dimensions. Our technique hopefully can also be applied to other indirect bandgap materials and use them in optical systems such as in artificial lighting system, CD and DVD players, and to improve depth-resolved images in flat panel display.
Speaker: Dr. Yang Hui Ying (Singapore University of Technology and Design, Singapore)
Time: 2:00-4:00PM, August 21 (Tuesday)
Place: Dr. Poe Lecture Hall, IAMS (原分所浦大邦講堂 臺大校園內)
Contact: Dr. Lain-Jong Li 李連忠博士
Dr. Yang Hui Ying is one of the pioneering batch faculty members of SUTD. Her current research interests and projects include the development of metal oxide and carbon nanomaterials based solid state lighting, water purification membrane and energy storage devices. Since year 2005, Dr. Yang has published more than 78 peer-reviewed articles in many prestigious international journals including Adv. Mater., Adv. Func. Mater., ACS Nano, Small, Appl. Phys. Lett., Nanoscale, and ACS Appl. Mater. Interfaces, which have been cited over 968 times. Dr. Yang was the recipient of the prestigious Lee Kuan Yew Fellowship (2008), Singapore Millennium Foundation Fellowship (2006), L’Oreal Singapore for Women in Science national Fellowship (2010), Chinese Government Award for Outstanding Self-Financed Students Abroad (2005), Second Prize in MRS Science-as-Art Competition (2008), and First Prize in NTU Nanoscience-as-Art Competition (2005). She and her research works have been highlighted by many international and local Medias, such as Discovery Channel, Channel News Asia, Straits times, Wall Street Journals, etc.
【Abstract】
The research and innovation in novel lighting technology based on solid state lighting (i.e., organic and inorganic light emitting diodes (LEDs)) are of central industrial and social relevance. LEDs present many advantages over conventional light bulbs and incandescent light sources, such as lower energy consumption, longer lifetime, improved robustness, smaller size, and greater durability. Semiconductor nanowires with wide bandgap are important materials for the development of transparent diodes and transistors, photovoltaic devices, and liquid crystal displays. Recently, we discovered that the defect states induced inside the surface of nanostructured SnO2 semiconductor supports huge amount of radiative excitonic recombination centres. In contrast to conventional light emitting materials, SnO2 and a group of transparent metal oxide materials (i.e., ITO, In2O3, TiO2, GeO2, Cu2O, CuCrO2, etc) have either dipole-forbidden transition or indirect bandgap which limited the further development of transparent electroluminescent technologies for the upcoming application in transparent display. In addition, weakly bound excitons, which generated inside the surface defect states of SnO2 nanowires, supported intensive ultraviolet stimulated emission via giant-oscillator-strength effect. It is also found that the weakly bound excitons and emission wavelength can be controlled by modifying the surface geometry of the nanostructured semiconductors. This is equivalent to achieve spatial and quantum confinement of excitons into nanoscale dimensions. Our technique hopefully can also be applied to other indirect bandgap materials and use them in optical systems such as in artificial lighting system, CD and DVD players, and to improve depth-resolved images in flat panel display.