1997 Fiscal Year Final Research Report Summary
Development of Photon Atomic Force Microscope
| Project/Area Number |
08554007
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 展開研究 |
|---|
| Research Field |
固体物性Ⅰ(光物性・半導体・誘電体)
|
|---|
| Research Institution | Osaka University |
|---|
Principal Investigator |
SUGAWARA Yasuhiro Osaka Univ., Faculty of Engineering, Associate Professor, 工学部, 助教授 (40206404)
|
|---|
| Project Period (FY) |
1996 – 1997
|
| Keywords | photon / atomic force microscope / near-field optics / evanescent field / force / electron-hole pair creation / electrostatic force / ultrahigh vacuum |
|---|
| Research Abstract |
1) By using the noncontact mode atomic force microscope with frequency modulation (FM) detection method in a high vacuum, the force gradient induced by the evanescent field was detected. There are two advantages of this method. One is high sensitivity as a force sensor. The other is that the local force gradient can be estimated without influence of capillary force due to water film on the prism surface. Using this method, we measured the force gradient distance curve induced by the evanescent field. We measured the incident beam intensity and bias voltage dependence of the force gradient induced by the evanescent field. As a result, we confirmed the surface photo-voltage (SPV) model. Furthermore, using the SPV model, we explained the results of the distance and polarization dependence of the force gradient.
2) We demonstrated a novel method to detect the van der Waals force gradient and the force gardient induced by the optical evanescent field on the surface simultaneously with high resolution, using the noncontact mode atomic force microscopy with frequency modulation detection method. The force gradient due to the evanescent field could be enhanced by applying the bias voltage. Polystirene latex spheres with 100 nm diameter were observed with spatial resolution better than 50 nm (lambda/14). Minimum detectable frequency shift of the cantilever was 0.09 Hz, by which the minimum detectable values of the force gradient and force due to the evanescent field were estimated to be under 3.8x10^<-5> N/m and 0.66 pN,respectively.
|
