Rare Earth:Photoconductors for Terahertz Generation and Detection

• Applicants: Professor Dr. Gregor Koblmüller; Professor Dr. Sascha Preu
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering ; Experimental Condensed Matter Physics
• Term: from 2015 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 278381540

• Final Report Year: 2024

Final Report Abstract

The aim of REPHCON was the development of high-performance photoconductive terahertz sources and detectors based on ErAs:In(Al)GaAs. The photoconductors are operated with 1550 nm or 1030-1060 nm laser systems, both targetting continuous wave and pulsed operation. The research activities included in particular material physics research on optimizing the photo-conducting semiconductor material for terahertz applications, electrotechnical research that considered optimal antenna and electrode structures, questions from optics regarding the outcoupling of the Terahertz wave and in-coupling of the optical laser signal as well as system-level research in terms of integration into easily usable packages for their application in experiments. The 1st part of the project was carried out at the TUDa (FG Preu), the 2nd phase in cooperation of TUDa with TUM (FG Koblmüller). The photoconductors developed are now amongst the best worldwide. The following list summarizes the main results: Successful development of photoconductors for continuous wave operation at 1550 nm, both as a source and as a receiver. To the best of the applicants' knowledge, we achieved the largest published dynamic range to date of 52 dB with a continuous wave system and solely photoconductors at 1550 nm. Lowest published noise floor to date at room temperature of 1.8fW/Hz at 188 GHz. - System consisting of antenna-coupled pulsed photoconductors and a state-of-the-art 1550 nm pulsed laser system with a dynamic range of 110 dB (1 min. measurement time), 472μW THz power with ~45 mW laser power and > 6.5 THz bandwidth. - Demonstration of operation at 1030 nm. Fiber-coupled packages for both sources and receivers. - Transfer of growth to a molecular beam epitaxy facility in Germany.

Publications

• Pulsed THz time domain system with ErAs:In(Al)GaAs photoconductors. 2016 41st International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz), 1-2.
  Aller, Mario Mendez; de Jesus, Fernandez Olvera Anuar; Lu, Hong; Gossard, Arthur C. & Preu, Sascha
  
• Continuous-wave 1550 nm operated terahertz system using ErAs:In(Al)GaAs photo-conductors with 52 dB dynamic range at 1 THz. Optics Express, 25(23), 29492.
  Olvera, A.D.J. Fernandez; Lu, H.; Gossard, A. C. & Preu, S.
  
• Dispersive properties of self-complementary log-periodic antennas in pulsed THz systems. 2017 42nd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 1-2.
  Fernandez, Olvera A. D. J.; Nandi, U.; Norman, J.; Gossard, A. C.; Roskos, H. & Preu, S.
  
• 1.5 Port Vector Spectrometer for Terahertz Time Domain Spectroscopy. 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 1-2.
  Faridi, Fahd R.; Nandi, Uttam & Preu, Sascha
  
• 1550-nm Driven ErAs:In(Al)GaAs Photoconductor-Based Terahertz Time Domain System with 6.5 THz Bandwidth. Journal of Infrared, Millimeter, and Terahertz Waves, 39(4), 340-348.
  Nandi, U.; Norman, J. C.; Gossard, A. C.; Lu, H. & Preu, S.
  
• Continuous-Wave Terahertz System with 50 dB Dynamic Range at 1 THz Using a n-i-pn-i-p Superlattice Photomixer and an ErAs: InGaAs Photoconductor Operated at 1550 nm. 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 1-2.
  Aller, Mario Mendez; Lu, Hong; Gossard, Arthur C. & Preu, Sascha
  
• ErAs Enhanced Active Photonic THz Components. 2018 First International Workshop on Mobile Terahertz Systems (IWMTS), 1-4.
  Aller, M. Mendez; Lu, H.; Gossard, A.C.; Nandi, U.; Norman, J.C. & Preu, S.
  
• Antenna-coupled spintronic terahertz emitters driven by a 1550 nm femtosecond laser oscillator. Applied Physics Letters, 115(2).
  Nandi, U.; Abdelaziz, M. S.; Jaiswal, S.; Jakob, G.; Gueckstock, O.; Rouzegar, S. M.; Seifert, T. S.; Kläui, M.; Kampfrath, T. & Preu, S.
  
• Characterization of a Terahertz Isolator using a 1.5 Port Vector Spectrometer. 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 1-2.
  Faridi, Fahd R. & Preu, Sascha
  
• Continuous-Wave Electro-Optic Terahertz Dual-Comb Operating from 0.096 to 0.496 THz Using ErAs:In(Al)GaAs Photoconductors. 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 1-3.
  Fernandez, Olvera Anuar D. J.; Betancur, Andres F.; Dios, Cristina de; Preu, Sascha & Acedo, Pablo
  
• Effect of DC Electric Field on the Emitted THz Signal of Antenna-Coupled Spintronic Emitters. 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 1-2.
  Nandi, U.; Preu, S.; Abdelaziz, M.S.; Jaiswal, S.; Jakob, G.; Gueckstock, O.; S, Rouzegar M. R.; Seifert, T.S.; Klaui, M. & Kampfrath, T.
  
• High Dynamic Range THz Systems using ErAs:In(Al)GaAs Photoconductors. 2019 IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes for RF and THz Applications (IMWS-AMP), 115-117.
  Nandi, Uttam; Faridi, Fahd R.; Olvera, Anuar D. J. Fernandez; Norman, Justin; Lu, Hong; Gossard, Arthur C. & Preu, Sascha
  
• International System of Units (SI) Traceable Noise-Equivalent Power and Responsivity Characterization of Continuous Wave ErAs:InGaAs Photoconductive Terahertz Detectors. Photonics, 6(1), 15.
  Fernandez, Olvera Anuar; Roggenbuck, Axel; Dutzi, Katja; Vieweg, Nico; Lu, Hong; Gossard, Arthur & Preu, Sascha
  
• System Integration and Packaging of a Terahertz Photodetector at $W$ -Band. IEEE Transactions on Components, Packaging and Manufacturing Technology, 9(8), 1486-1494.
  Dong, Yunfeng; Johansen, Tom Keinicke; Fernandez, Olvera Anuar de Jesus; Morales, Alvaro; Aller, Mario Mendez; Preu, Sascha; Zhurbenko, Vitaliy; Hanberg, Peter Jesper; Okonkwo, Chigo & Monroy, Idelfonso Tafur
  
• Terahertz Time-Domain Spectroscopy Based on Commercially Available 1550 nm Fabry–Perot Laser Diode and ErAs:In(Al)GaAs Photoconductors. Applied Sciences, 9(13), 2704.
  Tybussek, Kai-Henning; Kolpatzeck, Kevin; Faridi, Fahd; Preu, Sascha & Balzer, Jan C.
  
• Continuous Wave THz System Based on Dual Wavelength Monolithic Y-Branch Laser Diode. 2020 22nd International Conference on Transparent Optical Networks (ICTON), 1-4.
  Surkamp, Nils; Gerling, Alexandra; O'Gorman, James; Honsberg, Martin; Schmidtmann, Sebastian; Nandi, Uttam; Preu, Sascha; Sacher, Joachim; Brenner, Carsten & Hofmann, Martin R.
  
• ErAs:In(Al)GaAs photoconductor-based time domain system with 4.5  THz single shot bandwidth and emitted terahertz power of 164  µW. Optics Letters, 45(10), 2812.
  Nandi, Uttam; Dutzi, Katja; Deninger, Anselm; Lu, Hong; Norman, Justin; Gossard, Arthur C.; Vieweg, Nico & Preu, Sascha
  
• Performance of a 1030 nm driven ErAs: InGaAs photoconductive receiver at high THz average power. 2020 45th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 1-2.
  Nandi, U.; Vogel, T.; Mansourzadeh, S.; Hoffmann, M.; Norman, J. C.; Lu, H.; Gossard, A. C.; Saraceno, C. J. & Preu, S.
  
• A True Optoelectronic Spectrum Analyzer for Millimeter Waves With Hz Resolution. IEEE Access, 9(2021), 114339-114347.
  Fernandez, Olvera Anuar De Jesus; Krause, Benedikt Leander & Preu, Sascha
  
• Characterization of a Crossed Dipole Resonator Array using a Pulsed Free Space Two-Port Photonic VNA. 2021 46th International Conference on Infrared, Millimeter and Terahertz Waves (IRMMW-THz), 1-2.
  Faridi, Fahd R. & Preu, Sascha
  
• Current tuned slotted Y‐branch laser for wafer thickness measurements with THz radiation. Electronics Letters, 57(24), 936-938.
  Surkamp, N.; Gerling, A.; O'Gorman, J.; Honsberg, M.; Schmidtmann, S.; Nandi, U.; Preu, S.; Sacher, J.; Brenner, C. & Hofmann, M. R.
  
• Frequency Selective Optoelectronic Downconversion of a Terahertz Pulse Using ErAs:In(Al)GaAs Photoconductors. IEEE Access, 9(2021), 95391-95400.
  Olvera, Anuar de Jesus Fernandez; Krause, Benedikt Leander; Betancur-Perez, Andres; Nandi, Uttam; de Dios, Cristina; Acedo, Pablo & Preu, Sascha
  
• Material properties and performance of ErAs:In(Al)GaAs photoconductors for 1550 nm laser operation. Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, 39(2).
  Nandi, U.; Mohammadi, M.; Lu, H.; Norman, J.; Gossard, A. C.; Alff, L. & Preu, S.
  
• Pulsed free space two-port photonic vector network analyzer with up to 2 THz bandwidth. Optics Express, 29(8), 12278.
  Faridi, Fahd Rushd & Preu, Sascha
  
• Wavelength conversion through plasmon-coupled surface states. Nature Communications, 12(1).
  Turan, Deniz; Lu, Ping Keng; Yardimci, Nezih T.; Liu, Zhaoyu; Luo, Liang; Park, Joong-Mok; Nandi, Uttam; Wang, Jigang; Preu, Sascha & Jarrahi, Mona
  
• 1030 nm optimized photoconductive receiver excited with >20 mW of THz average power. 2022 47th International Conference on Infrared, Millimeter and Terahertz Waves (IRMMW-THz), 1-2.
  Vogel, Tim; Mansourzadeh, Samira; Schulz, Romina S.; Nandi, Uttam; Preu, Sascha & Saraceno, Clara J.
  
• A Comparison of Continuous-Wave and Pulsed Free Space 2-Port Photonic Vector Network Analyzers for Terahertz Characterization. 2022 47th International Conference on Infrared, Millimeter and Terahertz Waves (IRMMW-THz), 1-2.
  Faridi, Fahd R.; Fernandez, Olvera Anuar D. J.; Mukherjee, Amlan k. & Preu, Sascha
  
• Bias-Dependent Carrier Dynamics and Terahertz Performance of ErAs:In(Al)GaAs Photoconductors. IEEE Transactions on Terahertz Science and Technology, 12(4), 353-362.
  Nandi, Uttam; Scheer, Moritz; Lu, Hong; Norman, Justin C.; Gossard, Arthur C. & Preu, Sascha
  
• Slotted Y-branch laser for cw-THz thickness measurements at 1 THz. Novel In-Plane Semiconductor Lasers XXI, 6.
  Surkamp, Nils; Gerling, Alexandra; O'Gorman, James; Honsberg, Martin; Schmidtmann, Sebastian; Nandi, Uttam; Preu, Sascha; Sacher, Joachim; Brenner, Carsten & Hofmann, Martin R.
  
• THz metrology with monolithic tunable two-color diode lasers. Terahertz Photonics II, 16.
  Hofmann, Martin R.; Surkamp, Nils; Gerling, Alexandra; O'Gorman, James; Honsberg, Martin; Schmidtmann, Sebastian; Nandi, Uttam; Preu, Sascha; Sacher, Joachim & Brenner, Carsten
  
• Ultrafast carrier dynamics in terahertz photoconductors and photomixers: beyond short-carrier-lifetime semiconductors. Nanophotonics, 11(11), 2661-2691.
  Lu, Ping-Keng; Fernandez, Olvera Anuar de Jesus; Turan, Deniz; Seifert, Tom Sebastian; Yardimci, Nezih Tolga; Kampfrath, Tobias; Preu, Sascha & Jarrahi, Mona
  
• Performance of Photoconductive Receivers at 1030 nm Excited by High Average Power THz Pulses. IEEE Transactions on Terahertz Science and Technology, 14(2), 139-151.
  Vogel, Tim; Mansourzadeh, Samira; Nandi, Uttam; Norman, Justin; Preu, Sascha & Saraceno, Clara J.