Context: The structure of QD-LEDs used for the electrical-excitation scheme is similar to basic design of OLEDs. A layer of quantum dots is sandwiched between layers of electron-transporting and hole-transporting materials. An applied electric field causes electrons and holes to move into the quantum dot layer and recombine forming an exciton that excites a QD. This scheme is commonly studied for quantum dot display. The tunability of emission wavelengths and narrow bandwidth is also beneficial as excitation sources for fluorescence imaging. Fluorescence near-field scanning optical microscopy (NSOM) utilizing an integrated QD-LED has been demonstrated.

Question: What is one scheme of Quantum Dot excitation?
Answer: electrical-excitation

Question: What is one material used in electrical-excitation?
Answer: hole-transporting materials

Question: During the electrical-excitation scheme, what moves into the quantum dot layer?
Answer: electrons and holes

Question: A Quantum Dot LED has been used in what?
Answer: near-field scanning optical microscopy (NSOM)

Question:  What is one scheme of non-Quantum Dot excitation?
Answer: Unanswerable

Question:  What is one material used in non-electrical-excitation?
Answer: Unanswerable

Question: During the electrical-excitation scheme, what moves into the non-quantum dot layer?
Answer: Unanswerable

Question:  A Quantum Dot non-LED has been used in what?
Answer: Unanswerable