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Dr. Allan Bracker

Electronics Science and Technology Division
Naval Research Laboratory, Washington, DC 20375

November 29th, 3:30 PM

Thirkield Hall (Physics), room 103


Semiconductor Quantum Dots for Quantum Technologies

In recent years, scientists and engineers have begun to harness quantum effects such as superposition and entanglement for dramatic new technologies in computing, communication, and sensing. A variety of physical systems are under investigation, including atoms, photons, superconductors, and semiconductors. In this presentation, I will give an overview of work at the Naval Research Laboratory to develop semiconductor quantum dots for quantum technologies. Quantum dots are small semiconductor crystals of indium gallium arsenide (InGaAs) containing around ten thousand atoms, embedded in a larger crystal of GaAs. Using a variety of crystal growth and nanofabrication techniques, we can control their electronic and optical properties and build more complex structures such as quantum dot arrays and “molecules”. By embedding the quantum dots in a diode heterostructure, we gain the ability to inject individual electrons, and the electron spin is used as a quantum memory. We have demonstrated simple quantum logic gates by using laser pulses to manipulate the electron spin, and we are investigating how quantum dots can be used as a motion sensor and an on-demand single photon source.


Refreshments will be served at 3:30pm