PROGRAM

BN Seminar - Andrew Chernev (St.Petersburg Academic University): 'DNA detection by THz pumping'

Date:

Time:

10:00 hrs

Location:

A1.100

 

A new method of DNA detection is presented. It is based on the self-resonant modes excitation of single-stranded oligonucleotides with a silicon nanosandwich pump device. Resonant modes of oligonucleotides correspond to the unique combination of the nucleotide sequence and entire molecular shape. The suggested detection method is based on the interaction of the silicon nanosandwich with nucleic acids deposited on its surface. The silicon nanosandwich represents an ultra-narrow, p-type silicon quantum well (Si-QW) confined by delta barriers heavily doped with boron on the n-Si (100) wafer. The edge channels of this Si-QW have been shown to be an effective source of THz emission caused by the presence of the negative-U dipole boron centers [1]. Corresponding system of microcavities is introduced into the Si-QW plane to increase the selective THz line emission [1]. Such devices allow for the creation of THz spectra that are similar to the self-resonant modes of oligonucleotides [2]. Thus, the excitation of the self-resonant modes of the oligonucleotides deposited in the Si-QW plane becomes possible and provides feedback that gives rise to the changes in the conductance of the edge channels [3].

[1]. N.T. Bagraev, V.A. Mashkov, et.al, Appl. Magn. Reson., v.39, p.113 (2010).

[2]. B.M. Fischer, M. Walther, P.Uhd. Jepsen, Phys. Med. Biol. v.47, p.3807 (2002).

[3]. N.T. Bagraev , A.L. Chernev et. al., Semiconductors, v.50(9), p.1208 (2016).