Violet to deep-ultraviolet InGaN∕GaN and GaN∕AlGaN quantum structures for UV electroabsorption modulators

Abstract

In this paper, we present four GaN based polar quantum structures grown on c-plane embedded in p-i-n diode architecture as a part of high-speed electroabsorption modulators for use in optical communication (free-space non-line-of-sight optical links) in the ultraviolet (UV): the first modulator incorporates ∼4–6nm thick GaN∕AlGaN quantum structures for operation in the deep-UV spectral region and the other three incorporate ∼2–3nm thick InGaN∕GaN quantum structures tuned for operation in violet to near-UV spectral region. Here, we report on the design, epitaxial growth, fabrication, and characterization of these quantum electroabsorption modulators. In reverse bias, these devices exhibit a strong electroabsorption (optical absorption coefficient change in the range of 5500–13000cm−1 with electric field swings of 40–75V∕μm) at their specific operating wavelengths. In this work, we show that these quantum electroabsorption structures hold great promise for future applications in ultraviolet optoelectronics technology such as external modulation and data coding in secure non-line-of-sight communication systems.

Ultraviolet optoelectronic devices based on AIGaN alloys grown by molecular beam epitaxy

“…[30][31][32][33][34][35][36] In these materials, strong electric fields are already present in the QWs due to spontaneous and piezoelectric polarizations; as a result, an even greater change in absorption is achievable, especially if the internal fields are compensated by the external bias so that the net field in the QWs is reduced. Such devices are likely to find a number of applications.…”

“…[21][22][23][24][25][26][27][28][29] UV electroabsorption modulators have generally received much less attention. [30][31][32][33][34][35][36] In this paper, we review progress in developing UV optoelectronic devices based on AlGaN alloys grown by plasmaassisted molecular beam epitaxy (PAMBE). These include LEDs, lasers, photodetectors, electroabsorption modulators, and distributed Bragg reflectors (DBRs).…”

Tuning shades of white light with multi-color quantum-dot–quantum-well emitters based on onion-like CdSe–ZnS heteronanocrystals

“…Adequate amounts of the Zn (Cd) and S (Se) solutions required for one shell growth are added to the core [28,29]. We first grow a 14 nm thick GaN nucleation layer and a 200 nm thick GaN buffer layer.…”

Self-consistent analysis of electron transport in GaN/AlGaN super lattice nanostructure for light emission

“…The large band gap and mechanical hardness, strong inter-atomic bond of III-V nitride semiconductor based devices pertinent to operate at elevated temperature, enhanced performance, high speed and reliability [1][2][3][4] for microelectronics and high power applications. The nitride based semiconductors has shown a superior applicability in the visible to ultraviolet [5][6][7] spectral range and hence they are extensively studied for electronic and optoelectronic applications.…”