17 research outputs found
Femtosecond Coherence and Quantum Control of Single Molecules at Room Temperature
Quantum mechanical phenomena, such as electronic coherence and entanglement,
play a key role in achieving the unrivalled efficiencies of light-energy
conversion in natural photosynthetic light-harvesting complexes, and triggered
the growing interest in the possibility of organic quantum computing. Since
biological systems are intrinsically heterogeneous, clear relations between
structural and quantum-mechanical properties can only be obtained by
investigating individual assemblies. However, single-molecule techniques to
access ultrafast coherences at physiological conditions were not available so
far. Here we show by employing femtosecond pulse-shaping techniques that
quantum coherences in single organic molecules can be created, probed, and
manipulated at ambient conditions even in highly disordered solid environments.
We find broadly distributed coherence decay times for different individual
molecules giving direct insight into the structural heterogeneity of the local
surroundings. Most importantly, we induce Rabi-oscillations and control the
coherent superposition state in a single molecule, thus performing a basic
femtosecond single-qubit operation at room temperature