بخشی از پاورپوینت
اسلاید 1 :
Historical Review
¡1929: The concept of laser cooling was established.
¡1960: Laser was invented.
¡1995: Laser cooling was first observed in ytterbium-doped glass.
¡????: Laser cooling in semiconductors is achieved.
اسلاید 2 :
Significance
¡Heating is a major problem in semiconductor devices.
¡Optical refrigerator using laser cooling will be free of vibration, mechanically robust and compact.
¡ It has far reaching implications in the area of optical detection systems and optoelectronic devices.
اسلاید 3 :
Purpose
¡invent a practical all-solid-state optical refrigerator to cool semiconductors using laser cooling.
¡We hypothesize that laser cooling in semiconductors can achieve temperatures ~10K and below
اسلاید 4 :
Overview of Methodology
- Develop a comprehensive theoretical model of laser cooling in semiconductors.
- Grow new semiconductor materials optimized for laser cooling using MOCVD
- Demonstrate experimentally the theory of laser cooling in semiconductor devices.
- Build prototype optical refrigerator in semiconductors.
اسلاید 5 :
Step 1: Develop a comprehensive theoretical model of laser cooling in semiconductors.
¡Two key issues, luminescence trapping and red-shifting, have not been addressed in the current theory and these issues will frustrate our attempts to achieve semiconductor net cooling
اسلاید 6 :
Luminescence Trapping
¡Total internal reflection
اسلاید 7 :
Step1: Deliverable
¡understanding of which materials are optimum for laser cooling in semiconductors.
¡predict the possible designs of the future optical refrigerators.
اسلاید 8 :
Step 2: Use MOCVD to grow new semiconductor materials
¡InGaP/GaAs Heterostructures have been predicted to be good candidates for laser cooling in semiconductors.
¡perform microscopic analysis of each material in order to optimize the materials for laser cooling.
اسلاید 9 :
Step2: Deliverable
¡optimal materials that have a good chance of achieving net cooling.
اسلاید 10 :
Step 3: Demonstrate experimentally the theory of laser cooling in semiconductor devices
¡Do experiment to prove laser cooling in semiconductors