Enhancing Quantum Dot Emitters by Precisely Positioned Micrometric SILs

Using interferometric closed loop scanning integrated into the attoCFM I confocal microscope for cryogenic in-situ lithography, the group of P. Michler in Stuttgart was able to optically localize quantum dots (QDs) with a unprecedented precision of 2 nm and mark them via lithography.
This procedure enables further processing and optimizing these single photon emitters to enhance light extraction. In this case, they successfully demonstrated how to precisely add hemispherical lenses directly on top of the quantum dot via 3D direct laser writing. This led to an enhancement in extraction efficiency by a factor of 2.

“Our attoCFM I LT-lithography setup is not only the best choice when it comes to stability requirements. Its closed loop scanning feature also allows us to optically pre-select quantum dots suitable for desired experiments and mark them in-situ via lithography with nanometric precision.”
Prof. Dr. Peter Michler (University of Stuttgart, Germany)

This measurement was realized with the attoCFM I, and the Low Temperature Photolithography.

Enhancing Quantum Dot Emitters by Precisely Positioned Micrometric SILs cryogenic confocal microscopy attoCFM I  closed loop scanning  cryogenic photolithography
Enhancing Quantum Dot Emitters by Precisely Positioned Micrometric SILs cryogenic confocal microscopy attoCFM I  closed loop scanning  cryogenic photolithography