Blue quantum electroabsorption modulators based on reversed quantum confined Stark effect with blueshift

The authors present the design, growth, fabrication, experimental characterization, and theoretical analysis of blue quantum electroabsorption modulators that incorporate $∼5nm$ thick $In0.35Ga0.65N∕GaN$ quantum structures for operation between 420 and $430nm$⁠. Growing on polar $c$ plane on sapphire, they obtain quantum structures with zigzag potential profile due to alternating polarization fields and demonstrate that their optical absorption blueshifts with applied electric field, unlike the redshift of conventional quantum confined Stark effect. In $InGaN∕GaN$ quantum structures, they report the largest absorption change of $6000cm−1$ for $6V$ bias swing around $424nm$⁠, holding promise for blue optical clock generation and injection directly into silicon chips.