Transferring a biomolecule and its biomimetic surrounding into the gas phase for explorations and applications of quantum interference is a non-trivial task.
A number of criteria have to be satisfied:
- The molceular ensemble shall be neutral in order to prevent decoherence due to interactions with fluctuating electric stray fields.
- It needs to mass-selected and monochromatic if we require in a narrow band of de Broglie wavelengths
- It shall not exceed a momentum of p < 10^6 AMU x m/s to be compatible with existing KDTL and OTIMA matter-wave interferometers in the QuNaBioS/QNP laboratories.
- It shall be isolated from unwanted decoherence channels.
We address these problems by adapting known techniques to our needs, such as
- Effusive sources
- Laser induced acoustic desorption (LIAD),
- Matrix assisted laser desorption (MALD),
- Electro-spray ionization (ESI),
- Supersonic expansions,
- Cryogenic buffer gas cells
- Cold ion traps
At the same time we need to address the detectability of large biomolecules with regard to efficiency, mass and conformation selectivity, and many other aspects. We are exploring:
- Direct postionization mass spectrometry
- Functionalization and tagging of high-mass biomolecules
- Sub-wavelength resolved single-molecule fluorescence
- Scanning probe detectors and more.