Local phonon imaging of AlN nanostructures with nanoscale spatial resolution.

We demonstrate local phonon analysis of single AlN nanocrystals by two complementary imaging spectroscopic techniques: tip-enhanced Raman scattering (TERS) and nano-Fourier transform infrared (nano-FTIR) spectroscopy. Strong surface optical (SO) phonon modes appear in the TERS spectra with their intensities revealing a weak polarization dependence. The local electric field enhancement stemming from the plasmon mode of the TERS tip modifies the phonon response of the sample, making the SO mode dominate over other phonon modes.

Determination of the Thermodynamic Parameters of DNA Double Helix Unwinding with the Help of Mechanical Methods.

For the first time, rupture event scanning (REVS) procedure based on quartz crystal microbalance (QCM) and involving only mechanical action was used to determine the height of the energy barrier for dsDNA unwinding. Melting point was determined with the help of this procedure. To determine the thermodynamic parameters including enthalpy, DNA denaturation was represented as a unimolecular process.

Temperature dependence of unwinding forces between complementary oligonucleotides.

Rupture Event Scanning (REVS) was used to study oligonucleotide unwinding under mechanical load. Oligonucleotide melting temperature was successfully estimated using this method. To estimate the enthalpy of reaction, we represented denaturation process as a unimolecular reaction.