A single molecule as a probe of optical intensity distribution

Area of Science:

• Molecular spectroscopy
• Scanning probe microscopy
• Low-temperature physics

Background:

• Single-molecule spectroscopy offers high sensitivity for probing material properties.
• Optical standing waves create nanoscale intensity variations.
• Precise positioning of molecules is crucial for advanced optical measurements.

Purpose of the Study:

• To identify and spatially map single terrylene molecules within p-terphenyl crystals.
• To demonstrate the capability of a single molecule as a nanometric probe.
• To explore future applications combining spatial and spectral single-molecule sensitivity.

Main Methods:

• Utilized fluorescence excitation spectroscopy at cryogenic temperatures (1.4 K).
• Employed a scanning-probe microscope to move a single molecule through a laser beam.
• Recorded fluorescence signals to map molecular position and intensity distribution.

Main Results:

• Successfully identified individual terrylene molecules embedded in p-terphenyl crystals.
• Mapped the intensity distribution of a one-dimensional optical standing wave using a single molecule.
• Demonstrated that a single molecule can act as a nanoscale probe.

Conclusions:

• Single terrylene molecules can be precisely located and utilized as probes in optical standing waves.
• The technique highlights the potential for combining high spatial and spectral resolution at the single-molecule level.
• Future research can leverage this approach for advanced nanoscale optical investigations.