中国激光, 2009, 36 (4): 978, 网络出版: 2009-04-27
低温生长砷化镓光电导天线产生太赫兹波
Terahertz Wave Generation with Low-Temperature-Grown GaAs Photoconductive Antennas
光谱学 太赫兹波 时域光谱测量 低温生长砷化镓 光电导天线 spectroscopy terahertz wave time domain spectroscopy measurement low-temperature-grown GaAs photoconductive antenna
摘要
宽频太赫兹(THz)技术在**、科研等领域有着广阔的应用前景,光电导天线是产生宽频THz波的重要手段。分析了低温生长和高温退火对光电导天线材料载流子寿命和电阻率的影响。在生长温度为230 ℃和250 ℃,退火温度为475 ℃的低温生长砷化镓(LTG-GaAs)上制备了领结(BowTie)和偶极子(Dipole)两种电极结构的小孔径光电导天线。实验给出, 在250 ℃生长的LTG-GaAs上制备的光电导天线产生的太赫兹波辐射强度和频谱宽度较好,谱宽达到了3.6 THz,BowTie天线的辐射强度优于Dipole天线。两种形状的光电导天线皆可在10 V的偏置电压下产生太赫兹波辐射。
Abstract
Broadband terahertz (THz) technology has widespread applications in the fields of national defense, scientific research and so on, and photoconductive antenna is an essential approach to generate THz wave. The impact of growing and annealing temperatures on material carrier lifetime and resistivity was analyzed. Four small-aperture photoconductive antennas of BowTie and Dipole structures were fabricated on low-temperature-grown GaAs (LTG-GaAs) grown at 230 ℃ and 250 ℃ respectively, and annealed at 475 ℃. As a result, the 250 ℃ grown antennas have higher THz wave output power and broader spectrum up to 3.6 THz, in contrast to the 230 ℃ grown one. In addition, the output power generated by BowTie antenna is stronger than Dipole antenna. Moreover, it is verified that both of the small-aperture photoconductive antennas can generate THz wave under 10 V bias voltage.
李铁元, 娄采云, 王黎, 黄缙, 赵国忠, 石小溪. 低温生长砷化镓光电导天线产生太赫兹波[J]. 中国激光, 2009, 36(4): 978. Li Tieyuan, Lou Caiyun, Wang Li, Huang Jin, Zhao Guozhong, Shi Xiaoxi. Terahertz Wave Generation with Low-Temperature-Grown GaAs Photoconductive Antennas[J]. Chinese Journal of Lasers, 2009, 36(4): 978.