- 著者
- Hattori Toshiaki
- 出版者
- American Institute of Physics
- 雑誌
- The journal of chemical physics (ISSN:00219606)
- 巻号頁・発行日
- vol.133, no.20, pp.204503, 2010-11
- 被引用文献数
- 9
A general theoretical framework of two-dimensional time-domain second-order and third-order terahertz spectroscopy has been presented. The theoretical treatment is based on a classical and phenomenological model with weak nonlinearities. Three types of nonlinearity sources, anharmonicity, nonlinear coupling, and nonlinear damping, were considered. The second-order THz spectroscopy has an exact correspondence to fifth-order off-resonance Raman spectroscopy, and it has been shown that the present treatment gives exactly the same results as of the quantum mechanical theory under the weak nonlinearity condition. General expressions for the nonlinear signal have been obtained for a single-mode system, and numerical calculations for delta-function incident terahertz pulses were shown. For the third-order signal, two-level systems were also considered for comparison. Contributions of two types of incident pulse sequences have been studied separately in the third-order signals. Profiles of the two-dimensional signals were found to depend on the origin and order of the nonlinearity and also on the pulse sequence. The results of the present study show that the two-dimensional signal features of second- and third-order nonlinear terahertz spectroscopy can clarify the nature of the system which is not accessible using linear spectroscopy.
- 著者
- Klemm Richard A. Delfanazari Kaveh Tsujimoto Manabu Kashiwagi Takanari Kitamura Takeo Yamamoto Takashi Sawamura Masashi Ishida Kazuya Hattori Toshiaki Kadowaki Kazuo
- 出版者
- Elsevier
- 雑誌
- Physica. C, Superconductivity and its applications (ISSN:09214534)
- 巻号頁・発行日
- vol.491, pp.30-34, 2013-08
- 被引用文献数
- 19 3
In order to understand the radiation observed from the intrinsic Josephson junctions in triangular Bi2Sr2CaCu2O8+δ mesas, we calculate the transverse magnetic (TM) electromagnetic modes for thin equilateral cavities. A new set of distinct but degenerate TM modes coexists with the known modes of Helszajn and James, but are expected to lead to distinct radiation angular distribution patterns. Although we have been unable to solve for the exact TM modes of a thin cavity of general acute isosceles triangular shape, we solved exactly the closely related problems of the TM cavity modes of two thin circumscribing “pie-shaped” wedges, which provide highly accurate approximations to very acute isosceles triangular cavities.
- 著者
- Hattori Toshiaki Sakamoto Masaya
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.90, no.26, pp.261106, 2007-06-25
- 被引用文献数
- 16
The authors have developed a method of real-time terahertz imaging in which image deformation due to nonuniformity of residual birefringence in the electro-optic (EO) sampling crystal is corrected. Real-time terahertz imaging using intense terahertz pulses and two-dimensional EO sampling can suffer from birefringence nonuniformity of the EO crystal since the birefringence is explicitly used for the linear detection of the terahertz field. In the proposed method, the distribution of the residual birefringence of the EO crystal is measured and used for image correction. Deformation-free images of the spatial profile of a focused terahertz pulse were obtained.