Semiconductor structures, low-dimensional systems, quantum phenomena

Improving the efficiency of photodetector structures based on Ge/Si quantum dots by photonic crystal modes in the mid-infrared range

A. A. Bloshkin^ab, A. I. Yakimov<sup>a

a</sup> Rzhanov Institute of Semiconductor Physics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
^b Novosibirsk State University, 630090 Novosibirsk, Russia

Abstract: The spatial distribution of the electromagnetic field of a light wave in Ge/Si heterostructures with Ge quantum dots on a silicon-on-insulator substrate coupled to a photonic crystal has been studied using mathematical modeling methods. The array of air holes served to convert the radiation incident along the normal to the surface into planar waveguide modes. The period of the photonic crystal ranged from 1.3 to 1.8 microns, the hole depth ranged from 100 to 1100 nm, and the hole diameter was 2/3 of the period of the structure. A series of optical resonances with multiple (up to 300 times) amplification of the intensity of the light wave field in the quantum dot layers in the wavelength range of 2–6 microns compared with the structure without holes has been detected. The optimal parameters of the structure (the period of the photonic crystal and the depth of the holes) have been determined, ensuring maximum amplification of the photo response.

Received: 10.04.2025
Revised: 18.06.2025
Accepted: 29.07.2025

DOI: 10.61011/FTP.2025.04.61257.7801