attoCFM II

fiber-based confocal microscope

miniaturized fiber-based confocal microscope head

ultimate drift stability at low temperatures

1 single mode fiber for excitation and detection

fast turnaround without optical alignment

closed loop scanning (optional)

easy retrieval of regions-of-interest


The attoCFM II is an ultra-stable fiber-based confocal microscope for use at low temperature and in high magnetic fields in reflection mode. Based on a single mode fiber and a fiber-based objective, it was designed for ultimate long-term stability: without free-beam optics entering the cryostat, and all optical elements well thermalized inside the cryostat and cold, there is basically no observable drift at all, and hence extended measurement periods even of several weeks are feasible. The wavelength range is obviously limited by the range of the single mode fiber used, but can be adapted by using different fibers for different ranges. Splitting of the excitation and detection signals is usually performed outside of the cryostat either with a fiber coupler or an optical splitter box. The easy handling and the outstanding longterm stability open up new possibilities in all quantum optics and spectroscopy applications in the sub-micron range.

The microscope uses a set of xyz-positioners for coarse positioning of the sample over a range of several mm, and a dedicated mechanically amplified piezo based xy scanner with a very large scan range even at cryogenic temperatures.

Optionally, the attoCFM II can be equipped with interferometric encoders for closed loop xy scanning with 1 nm resolution, and an ultra large range scanner with 125 μm scan range at 4 K. Being made from non-magnetic materials, the microscope is ideally suited for photoluminescence spectroscopy and other quantum optics applications in combination with high magnetic fields.

For data acquisition during scanning, our powerful and flexible ASC500 SPM controller with its open signal architecture can be used. It addresses the needs of experts to have control over all signals, while maintaining a very user-friendly software interface that also supports measurement routines based on LabVIEW scripts. All in- and output signals are accessible via front panel BNCs, and can hence easily be monitored, stored and used for additional control loops or spectroscopies. Finally, our unique closed loop scan option allows for global sample navigation over the complete range of the microscope at cryogenic temperatures, and hence enables the retrieval of regions of interest very precisely. For more info please refer to the fundamentals section.

Cryogenic Tablet


No SpecSheet available

Fields of Applications