Assistant Professor of Chemistry and Biochemistry

Office: Urey Hall 3250
Phone: 858-246-0511
Email: migalperin@ucsd.edu
Web: http://galperingroup.ucsd.edu
Group: View group members

2011

Hellman Faculty Fellow

2011

DOE Early Career Award

2007

LANL Director's Postdoctoral Fellowship

2001

The Israel Chemical Society, J. Jortner prize

1. Transport in molecular junctions.

One of distinct features of molecules as compared e.g. to quantum dots is their flexibility, so that inelastic effects in transport through molecular devices is more pronounced. Currently inelastic quantum transport through tunneling junctions at resonance can be treated properly only in the weak electron-vibration coupling (when coupling to contacts is much stronger than interactions on the bridge). The other extreme is usually treated either within semi-classical (master equation) approaches or is based on scattering theory considerations. In the last case electron-vibration coupling can be taken into account exactly (or numerically exactly), but all junction related information (Fermi seas in the contacts and their influence on the bridge processes) is lost. We try to develop theoretical techniques to improve quality of calculations in the strongly correlated regime. The last is of particular importance for practical applications (molecular switches, memory, optoelectronic devices etc.)

2. Molecular spectroscopy at non-equilibrium.

Spectroscopy is done usually in the language of molecular states, while ab initio scheme treat transport mostly at the level of effective single-electron orbitals. The goal is development of theoretical tools for description of non-equilibrium molecular systems in the language of many-body states. Accomplishing this task will take into account state-specific molecular properties: change of electronic structure of the molecule upon oxidation/reduction or excitation by external field, charge specific frequencies of vibrations, anharmonicities and non-Born-Oppenheimer couplings. It will also make possible to introduce standard quantum chemistry methods into description of molecular transport, and will treat of non-equilibrium state of the molecule (e.g. transport) and its interaction with light on the same footing.

Computational and Theoretical

Contour plot of conductance and second derivative of current for inelastic transport through quantum dot.

Schemes and diagrams for `normal' and `inverse' Raman scattering.

Comparison of NEGF, GQME, and Redfield QME.