Dixit Kirtan P, Gregory Don A
Department of Physics and Astronomy, The University of Alabama in Huntsville, 301 Sparkman Drive, Huntsville, AL, 35899, USA.
Discov Nano. 2023 Aug 11;18(1):100. doi: 10.1186/s11671-023-03879-5.
The attainment of dynamic tunability in spectrally selective optical absorption has been a longstanding objective in modern optics. Typically, Fabry-Perot resonators comprising metal and semiconductor thin films have been employed for spectrally selective light absorption. In such resonators, the resonance wavelength can be altered via structural modifications. The research has progressed further with the advent of specialized patterning of thin films and the utilization of metasurfaces. Nonetheless, achieving dynamic tuning of the absorption wavelength without altering the geometry of the thin film or without resorting to lithographic fabrication still poses a challenge. In this study, the incorporation of a metal-oxide-semiconductor (MOS) architecture into the Fabry-Perot nanocavity is shown to yield dynamic spectral tuning in a perfect narrowband light absorber within the visible range. Such spectral tuning is achieved using n-type-doped indium antimonide and n-type-doped indium arsenide as semiconductors in a MOS-type structure. These semiconductors offer significant tuning of their optical properties via electrically induced carrier accumulation. The planar structure of the absorber models presented facilitates simple thin-film fabrication. With judicious material selection and appropriate bias voltage, a spectral shift of 47 nm can be achieved within the visible range, thus producing a discernible color change.
在光谱选择性光吸收中实现动态可调谐性一直是现代光学领域长期以来的目标。通常，由金属和半导体薄膜组成的法布里 - 珀罗谐振器已被用于光谱选择性光吸收。在这种谐振器中，共振波长可以通过结构修改来改变。随着薄膜的特殊图案化的出现和超表面的利用，该研究取得了进一步进展。尽管如此，在不改变薄膜几何形状或不采用光刻制造的情况下实现吸收波长的动态调谐仍然是一个挑战。在本研究中，将金属 - 氧化物 - 半导体（MOS）结构纳入法布里 - 珀罗纳米腔被证明可在可见范围内的完美窄带光吸收器中实现动态光谱调谐。这种光谱调谐是通过在MOS型结构中使用n型掺杂的锑化铟和n型掺杂的砷化铟作为半导体来实现的。这些半导体通过电诱导的载流子积累对其光学性质进行显著调谐。所呈现的吸收器模型的平面结构便于简单的薄膜制造。通过明智的材料选择和适当的偏置电压，在可见范围内可实现47 nm的光谱位移，从而产生明显的颜色变化。
