| Title |
Enhanced terahertz sensing via on-chip integration of diffractive optics with InGaAs bow-tie detectors / |
| Authors |
Redeckas, Karolis ; Jakštas, Vytautas ; Bernatonis, Matas ; Tamošiūnas, Vincas ; Valušis, Gintaras ; Minkevičius, Linas |
| DOI |
10.3390/s25010229 |
| Full Text |
|
| Is Part of |
Sensors: Special issue topical advisory panel members' collection series: "terahertz sensors".. Basel : MDPI AG. 2025, vol. 25, iss. 1, art. no. 229, p. 1-13.. eISSN 1424-8220 |
| Keywords [eng] |
terahertz sensing ; bow-tie detectors ; on-chip integration ; Fresnel zone plates ; sensitivity enhancement |
| Abstract [eng] |
The practical implementation of terahertz (THz) imaging and spectroscopic sys- tems in real operational conditions requires them to be of a compact size, to have enhanced functionality, and to be user-friendly. This work demonstrates the single-sided integration of Fresnel-zone-plate-based optical elements with InGaAs bow-tie diodes directly on a semiconductor chip. Numerical simulations were conducted to optimize the Fresnel zone plate’s focal length and the InP substrate’s thickness to achieve constructive interference at 600 GHz, room-temperature operation and achieve a sensitivity more than an order of magnitude higher—up to 24.5 V/W—than that of a standalone bow-tie detector. Investi- gations revealed the strong angular dependence of the incident radiation on the Fresnel zone plate-integrated bow-tie diode’s response. These findings pave a promising avenue for the further development of single-sided integration of flat optics with THz detectors, enabling improved sensitivity, simplified manufacturing processes, and reduced costs for THz detection systems in a more compact design scheme. |
| Published |
Basel : MDPI AG |
| Type |
Journal article |
| Language |
English |
| Publication date |
2025 |
| CC license |
|
