Strong quantum-confined Stark effect in germanium quantum-well structures on silicon
Yu-Hsuan Kuo1, Yong Kyu Lee1, Yangsi Ge1, Shen Ren1, Jonathan E. Roth1, Theodore I. Kamins1'2, David A. B. Miller1 & James S. Harris1
Al/Ti
Al/Ti
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n
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Figure 2 Schematic diagram of a p-i-n diode. The cross-sectional view shows the structure of strained Ge/SiGe multiple quantum wells (MQWs) grown on silicon on relaxed SiGe direct buffers (not to scale). In the measurements, light from a monochromator is incident on the top surface (that is, in a 'surface-normal' configuration) on the open area inside the rectangular frame top electrode (that is, between the portions of the AITi n-contacts shown in this cross-section).
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0.88 0.9 Energy (eV)
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Figure 3 | Effective absorption coefficient spectra. Strong QCSE is observed at room temperature with reverse bias from zero to 4 V. The thickness for effective absorption coefficient calculations is based on the combination of Ge well and SiGe barrier thicknesses.
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Figure 2. Linear absorption spectrum of the Ge multiple quantum well structure. A schematic sketch of the electronic structure according to [18] is given on the right-hand side.