Free-beam confocal optics at Dry mK
confocal microscopy in dry dilution refrigerators
Confocal Free-Beam Microscopy at Dry mK
Due to recent advances in several fields of solid state physics, there is a
growing interest in performing quantum optics, quantum opto-mechanics
and other measurements in the sub-100 mK regime. For example, since a
few years, it has become possible to prepare macroscopic mechanical oscillators in their groundstate, which opens the door to sophisticated experiments which couple such quantum resonators to quantum dots, single
spins in diamond, or high-finesse optical cavities. Applications range from
single-molecule mass detection to magnetic resonance force detection of
single electron spins [1].
Other experiments utilize resonant fluoresence to directly measure the
power spectrum of a single quantum dot, photo conductivity, Kondo excitons, spin cooling or nuclei polarization. Also, optically detected magnetic resonance for magnetometry can benefit from ultra-low temperatures
(quantum spin hall effect, topological insulators).
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At the same time, realizing such experimental setups within closed-cycle
dilution refrigerators even f