2007 Fiscal Year Final Research Report Summary
Investigation on photo-induced voltage phenomena in metallic photonic crystal slabs
| Project/Area Number |
17340092
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Condensed matter physics I
|
|---|
| Research Institution | Tohoku University |
|---|
Principal Investigator |
ISHIHARA Teruya Tohoku University, Tohoku University, Graduate School of Science, Professor (60168250)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
IWANAGA Masanobu Graduate School of Science, 大学院・理学研究科, Assistant Professor (20361066)
|
|---|
| Project Period (FY) |
2005 – 2007
|
| Keywords | photo-induced voltage / photo-rectification / photonic crystal / photon drag effect / metal / linear momentum / angular momentum / metamaterial |
|---|
| Research Abstract |
We have found that photo-induced voltage was found to exist even for the normal incidence in metallic photons crystall slabs with asymmetric unit cell. This photo-voltage is dependent on wavelength It is found to be explained in terms of conservation of translational momentum among incident, reflection transmission, diffraction lights and electrons in metal. In fact, numerical calculation based on scattering matrix formalism readily explains the experimental spectra. We also measured photo-induced voltage for Au/almina/Au tri-layer structure with square array of holes, which exhibits negative index of refraction at certain wavelength range. It was experimentally found that at the negative index region, the mode has negative group velocity. The most important discovery in this research project is the transverse photo-voltage induced by circularly polarized light on 40nm-thick An film with square array of circular holes. The voltage changes its sign upon the change in sense of the circul
… More
ar polarization. We confirmed the effect by carrying out a numerical calculation. This transverse photo-voltage induced by circularly polarized light can be interpreted as a kind of Hall effect due to the DC magnetic field generated by the circular motion induced by circular polarization. From this point of view, we made polarization analysis of reflection and transmission light in order to estimate the angular momentum transferred from the light to the electrons. When circular polarized light is incident on the sample obliquely the reflection and transmission light becomes of ellipsoidal polarization- From ellipticity and azimth angle, we estimated angular momentum transferred to the electron. Angular momentum carried by diffracted beams were ignored because they are weak. In this project, we focused our attention to the photo-induced electromotive form induced in metallic photons crystal slabs and found that translational as well as angular momenta are responsible to the phenomena Thus we have opened up a new research field connecting photophysics and transport Phenomena. Less
|
