Project/Area Number |
24656018
|
Research Category |
Grant-in-Aid for Challenging Exploratory Research
|
Allocation Type | Single-year Grants |
Research Field |
Applied materials science/Crystal engineering
|
Research Institution | Osaka City University |
Principal Investigator |
NAKAYAMA Masaaki 大阪市立大学, 工学(系)研究科(研究院), 教授 (30172480)
|
Project Period (FY) |
2012-04-01 – 2014-03-31
|
Project Status |
Completed (Fiscal Year 2013)
|
Budget Amount *help |
¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000)
Fiscal Year 2013: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
Fiscal Year 2012: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
|
Keywords | テラヘルツ電磁波 / コヒーレント縦光学フォノン / 半導体エピタキシャル構造 / i-GaAs/n-GaAs構造 / GaAs/InAlAsひずみ多重量子井戸構造 / p-i-nダイオード構造(GaAs) / 内部電場制御 / フォノン分極 / コヒーレントLOフォノン / 時間分解テラヘルツ電磁波分光法 / i-GaAs/n-GaAsエピタキシャル構造 / LOフォノン分極 / 時間分解テラヘルツ電磁波分光 / GaAs/InAlAs歪み量子井戸構造 / ピエゾ電場 / 内部電場 / コヒーレントLOフォノン-プラズモン結合モード |
Research Abstract |
We have investigated the control mechanisms of the terahertz (THz) electromagnetic waves from coherent longitudinal optical phonons in semiconductor epitaxial structures with use of internal electric fields. It was found that the THz electromagnetic waves are markedly enhanced by a surface electric field due to surface Fermi level pinning in i-GaAs/n-GaAs epitaxial structures and by a piezoelectric field due to lattice strain in (11n)-oriented GaAs/In0.1Al0.9As strained multiple quantum wells via an increase in phonon polarization. Furthermore, it was demonstrated that the THz electromagnetic waves are continuously and drastically enhanced by an applied bias voltage, which controls the internal electric field, in a p-i-n diode structure of GaAs: This provides us a novel concept of a THz device.
|