Kazuharu Uchiyama

Quantum Coherent Dynamics Enhanced by Synchronization with Nonequilibrium Environments

We report the discovery of the anomalous enhancement of quantum coherent dynamics (CD) due to a non-Markovian mechanism originating from not thermal-equilibrium phonon baths but nonequilibrium cohe...

Nanometre-scale pattern formation on the surface of a photochromic crystal by optical near-field induced photoisomerization

We observed nanometre-scale optical near-field induced photoisomerization on the surface of a photochromic diarylethene crystal via molecular structural changes using an optical near-field assisted atomic force microscope. A nanometre-scale concavity was formed on the sample surface due to locally induced photoisomerization. By using this optical near-field induced local photoisomerization, we succeeded in generating a pattern of alphabet characters on the surface of the diarylethene crystal below the optical wavelength scale. Further, by exploiting the photochromism of the investigated material, erasure of the generated pattern was also confirmed, where the evolution of the pattern during erasure depended on the local spatial characteristics of the crystal. These experimental findings demonstrate the fundamental abilities of photochromic crystals in dynamic memorization in nanometre-scale light–matter interactions.

Nano-imaging for glia-synapse fine structures with a homemade near-field optical microscope

To investigate basic processes responsible for brain functions by nano-imaging, we have developed a near-field optical microscope and successfully visualized fine structures and snapshot of the states of astrocytes and neurons.